Restoring Vision Naturally
A c o m p l e t e g u i d e t o u n d e r s t a n d i n g a n d i m p r o v i n g y o u r e y e s i g h t n a t ur a l l y
Table of Contents D i s cl c l a im im e r . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 I n t ro r o d uc uc t i o n . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
W h a t i s V i s i o n ? . . . . . . . . . . . . .. . . . . . . . . . . . . .. . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . .. . . . . . . . . . . . . . . .. . 3 H e a l i n g t h e E y e s , N a t u r a l l y . . . . . . . . . . . . . . .. . . . . . . . . . . . . .. . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . 3 H o w t o P r o c e ed ed T h r o u g h t h e B o o k . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . 4 S e c t i o n 1 – U N D E R S T A N D I N G V I S I O N . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 C h a pt pt e r 1
H o w th t h e E ye y e W o r ks ks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
A n a t o m y o f t h e E y e . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . .. . . . . . . . . . . . . .. . . . . . . . . . . . . . . . .. . . . 6 W o r k i n g P r i n c i p l e o f t h e E y e . . . . . .. .. . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 F i e l d o f V i e w o f t h e H u m a n E y e . . . . . . . . . . . . . .. . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . .. . . . . . . . . 9 C h a pt pt e r 2
C o m mo m o n R e a s o n s f o r E y e s t ra ra i n . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 0
C a u s e s o f E y e s t r a i n . . . . . . . . . . . . .. . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . .. . . . . . . . . . . . . .. . . . . . . . . . 1 1 S y m p t o m s o f E y e S t r a i n . . .. .. . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . 1 2 P r e v e n t i ng n g E y e s t r a i n . . .. .. . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . 1 2 1.
Correcting Bad Habits .......... .......... ......... .......... .......... ......... 13
B r e a k i n g B a d H a b i t s . . . . . . .. . . . . . . . . . . . . . .. . . . . . . . . . . . . . . .. . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . 1 4 1.
Find a Good Habit to Replace Your Bad Habit ......... .......... ......... 14
2.
Eliminate Glare .......... .......... ......... .......... .......... ......... ........ 16
3.
Reduce the Contrast ......... ......... .......... .......... .......... ......... ... 17
4.
Toughen Your Eyes ......... .......... ......... .......... .......... .......... .... 17
5.
Rest Your Eyes ......... .......... .......... ......... .......... .......... ......... 17
6.
Focus from a Distance .......... .......... ......... .......... .......... ......... 18
Chapter 3
P o o r E y e s i g h t : F a c t s an a n d M is i s u n d e r s t a n d i ng ng s . . . . . . . . . . . . . . . . . . . . . . 1 9
M y t h s . . . . . . . . . . . . . .. . . . . . . . . . . . . . .. . . . . . . . . . . . . . . .. . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . .. . . . . . . . . . . 2 0 F a c t s . . . . . . . . . . . . .. . . . . . . . . . . . . .. . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . .. . . . . . . . . . . . . . . .. . . . . . . . . . . . . . 2 3 Chapter 4
T y p e s o f V i s i o n Pr P r o b l e m s a nd nd T h e i r S o l u t i o n s . . . . . . . . . . . . . . . . . . . . . 2 6
L o s s a n d I m p a i r me me n t o f V i s i o n . . . . . . . . . . . . .. . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . .. . . . . . . . . . . 2 7 W h a t C a u s e s Vi Vi s i o n L o s s ? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 8 Level of Visual Impairment ......... .......... .......... .......... ......... .......... . 28
V i s u a l D i s t u r ba ba n c e s . . . . . . . . . . . . . .. . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . .. . . . . . . . . . . . . .. . . . . . . . . . 2 9 1.
D i p l o p i a . . . . . . . . . . . . . . .. . . . . . . . . . . . . .. . . . . . . . . . . . . . . . .. . . . . . . . . . . . . .. . . . . . . . . . . . . . . . .. 3 0 C a u s e s o f D o u b l e V i s i o n ( D i p l o pi a ) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 0 T y p e s o f D i p l op i a . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 2
2.
H a l o V i s i o n . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . .. . . . . . . . . . . . . . . .. 3 3 Causes of Halo Vision.......... .......... ......... .......... .......... ......... ........ 33
3.
B l u r r e d V i s i o n . . . . . . . . . . . . . .. . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . .. . . . . . . . . . . . . .. . . . . . . . . . 3 3 Types of Blurred Vision .......... .......... ......... .......... .......... .......... .... 34 Symptoms of Blurred Vision................ .......... .......... .......... ......... ... 34 Causes of Blurred Vision ......... .......... ......... .......... .......... .......... .... 34
4.
C o l o r B l i n d n e s s . . . . . . . . . . . . . . .. . . . . . . . . . . . . .. . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . .. . . . . . . 3 5 Types of Color Blindness ......... .......... ......... .......... .......... .......... .... 35 D e f e c t s i n t h e Th r e e C o n e s . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 6 M i s si si n g C o n e . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . 3 7 Black and White ......... ......... .......... .......... .......... ......... .......... ...... 37 C a u s e s o f C o l o r B l i n d n e ss ss . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 8
5.
B l i n d n e s s . . . . . . . . . . . . .. . . . . . . . . . . . . .. . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . .. . . . . . . . . . . . . . . .. 3 8 Types of Blindness ................ .......... .......... ......... .......... .......... .... 39 Causes of Blindness ......... ......... .......... .......... ......... .......... .......... . 39 Risk of Blindness......... .......... .......... .......... ......... .......... .......... .... 39 Blindness in Infants ......... ......... .......... .......... ......... .......... .......... . 40 Symptoms of Visual Impairment i n Young Children ......... .......... ......... 41
6.
E y e P a i n . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . .. . . . . . . . . . . . . . . .. . . . . . 4 1 Types of Eye Pain .......... .......... ......... .......... .......... .......... ......... ... 41 Ocular Pain .......... ......... .......... .......... .......... ......... .......... .......... . 41 O r b i t a l Pa Pa i n . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 2
E y e C o n d i t i o n s . . . .. . . . . . . . . . . . . . .. . . . . . . . . . . . . . . .. . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . .. . . . . . . . . . 4 2 R e f r a c t i o n : W h a t i s i t ? . . . . . . . .. .. . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . .. . . . . . . . . . . . . .. . . . . . . . . . . . 4 3 P r e s b y o p ia ia . . . . . . . . . . . . .. . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . 4 3
How Does Presbyopia Occur? .......... ......... .......... .......... .......... ....... 44 Who May Be A ffected By Presbyopia? .......... .......... ......... .......... ...... 44 Symptoms of Presbyopia ......... .......... ......... .......... .......... .......... .... 44 How Can P resbyopia Be Diagnosed and Corre cted? ......... .......... ......... 44
M y o p i a ( N e a r s i gh gh t e d n e s s ) . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 5 How Does Myopia Develop? .......... .......... ......... .......... .......... ......... 45 Who May Be A ffected By Myopia? .......... .......... ......... .......... .......... . 45 Symptoms of Myopia ......... .......... .......... ......... .......... .......... ......... 46 How Can Myopia Be Diagnosed and Corrected? ......... .......... .......... .... 46
H y p e r o p i a ( F a r s i gh gh t e d n e s s ) . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . .. . . . . . . . . . . . . .. . . . . . . 4 7 How Does Hyperopia Develop? ......... .......... .......... ......... .......... ...... 47 Who May Be Affected By Hyperopia? ......... .......... .......... .......... ....... 47 Symptoms of Hyperopia .......... .......... ......... .......... .......... .......... .... 48 How Can H yperopia Be Diagnosed and Corrected? ....... .......... ......... ... 48
A s t i g ma ma t i s m . . . . . . . . . . . . . .. . . . . . . . . . . . . .. . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . .. . . 4 9 H o w D o e s A s t i g m a t i sm D e v e l o p ? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 9 Who May Be Affected By Astigmatism? ........ .......... ......... .......... ...... 49 S y m p t o m s o f A s t i g m a t is is m . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 0 How Can Astigmatism Be Diagnosed and Corrected? .. .......... .......... .... 50
G l a u c o m a . . . . . . . . . . . . . .. . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . .. . . . . . . . . . . . . .. . . . . . . . . . . . . . . . .. . . . . . 5 1 What is Glaucoma? .......... ......... .......... .......... .......... ......... .......... . 51 Risk of Glaucoma .......... .......... ......... .......... .......... .......... ......... ... 53 Symptoms of Glaucoma......... .......... .......... .......... ......... .......... ...... 54 T r e a t i n g Gl Gl a u c o m a . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 6 C a t a r a ct . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . .. . . . . . . . . . . . . . .. . . . . 5 7 C a u s e s o f C a t a r a c t D e ve ve l o p m e n t . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 7 Risk of Cataract ......... ......... .......... .......... .......... ......... .......... ...... 58 Symptoms of Cataracts ......... .......... .......... .......... ......... .......... ...... 58 Diagnosing Cataracts ............... .......... ......... .......... .......... ......... ... 59 Treating Cataracts ......... .......... ......... .......... .......... .......... ......... ... 59 P r e v e nt i o n . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . .. . . . . . . . . . . . . . .. . . . . . . . . . . . . . . .. . 6 0
A g e - R e l a t e d M a c u l a r D e g e n e ra ra t i o n . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 1
Types of Age-Related Macular Degeneration ........... ......... .......... ...... 61 Symptoms of Age-Related Macular Degeneration .......... ......... .......... . 63 Treating Macular Degeneration .......... .......... ......... .......... .......... .... 63 R i s k F a c t o rs rs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 4 C h a r l e s B o n n e t Sy n d r o m e . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 4
A m b l y op op i a . . . . . . . . . . . . .. . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . .. . . . . . . . . . . . . .. . . . . . . . . . . . . . . . .. . . . . . 6 5 Causes of Amblyopia ......... .......... .......... ......... .......... .......... ......... 65 Recognizing Amblyopia ......... .......... .......... .......... ......... .......... ...... 66 R i s k F a c t o rs rs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 7 T e s t s f o r D i a g n o si si n g A m b l y o p i a . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 7 Treating Amblyopia ......... ......... .......... .......... ......... .......... .......... . 67
P t o s i s ( D r o o p in in g E y e l i d s ) . . . . . . . . . . . . .. . . . . . . . . . . . . .. . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . .. . . . 6 8 Causes of Ptosis ......... ......... .......... .......... .......... ......... .......... ...... 69 S y m p t o m s of of P t o s i s . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 0 Treating Ptosis .......... ......... .......... .......... .......... ......... .......... ...... 70 Complications ......... .......... ......... .......... .......... .......... .......... ....... 71
C o n j u n c t i v i ti ti s . . . . . . . . . . . . . . .. . . . . . . . . . . . . .. . . . . . . . . . . . . . . . .. . . . . . . . . . . . . .. . . . . . . . . . . . . . . . .. 7 2 T y p e s o f C o n j u n c t i vi vi t i s . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 3 Symptoms of Conjunctivitis .......... .......... ......... .......... .......... ......... 74 Treating Conjunctivitis ......... .......... .......... .......... ......... .......... ...... 75
K e r a t o c o n u s . . . . . . . . . . . . . .. . . . . . . . . . . . . .. . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . .. . . 7 6 C a u s e s o f K e r a t o c on on u s . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 6 Symptoms and Diagnosis of Keratoconus ......... .......... .......... .......... .. 77 Treating Keratoconus .......... .......... ......... .......... .......... ......... ........ 78
R e t i n a l D e t a c h m en en t . . . . . . . . . . . . . .. . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 1 Causes of Retinal Detachment ......... ......... .......... .......... .......... ....... 81 S y m p t o m s o f R e t i n a l D e t a c hm hm e n t . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 2 Risk Factors ......... ......... .......... .......... .......... ......... .......... .......... . 82 Complications of Retinal Detachment ................ .......... .......... ......... 83 Treatment for Retinal Tears and Detachment .................. ......... ........ 83
E y e F l o a t e r s . . . . . . . . . . . . . .. . . . . . . . . . . . . .. . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . .. . . 8 5 W h y D o E y e F l o a t e r s Ap Ap p e a r ? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 5
Characteristics of Eye Floaters ......... .......... .......... ......... .......... ...... 85 What do they indicate? .......... .......... ......... .......... .......... .......... .... 86
D i a b e t i c R e t i n o p at at h y . . . . . . . . . . . . . . .. . . . . . . . . . . . . .. . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . .. . . . . . . 8 7 Causes of Diabetic Retinopathy .......... .......... ......... .......... .......... .... 87 Symptoms of Diabetic Retinopathy ......... .......... ......... .......... .......... . 88 Treatment of Diabetic Retinopathy .......... ......... .......... .......... ......... 88
D r y E y e S y n d r o m e ( K e r a t o c on on j u n c t i v i t i s S i c c a ) . . . . . . . . . . . . .. . . . . . . . . . . . . . .. . . . . . . 8 9 Causes of Dry Eye Syndrome ......... .......... ......... .......... .......... ......... 90 Symptoms of Dry Eye Syndrome .......... .......... ......... .......... .......... .... 91 Diagnosis and Treatment of Dry Eye Syndrome ........... .......... ......... ... 92 C h a pt p t e r 5 D r ug u g s H a r m f ul ul t o t h e E y e . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 5
A c n e M e d i c a t i o n . . . . . . . . . . . . .. . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . .. . . . . . . . . . . . . .. . . . . . . . . . . . . . . 9 6 1.
Isotretinoin .......... .......... ......... .......... .......... .......... ......... ... 96
2.
Minocycline .......... .......... ......... .......... .......... .......... ......... ... 96
A l z h e i m e r' r' s M e d i c a t i o n . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 7 1.
Cholinesterase Inhibitors .......... .......... ......... .......... .......... .... 97
A n t i b i o t i c s . . . . . . . . . . . . .. . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . .. . . . . . . . . . . . . .. . . . . . . . . . . . . . . . .. . . . . . 9 7 1.
F l u o r o q u i n ol ol o n e s . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 8
2.
Synthetic Penicillin .......... ......... .......... .......... .......... ......... ... 98
3.
Terbinafine......... .......... .......... .......... ......... .......... .......... .... 98
4.
Tetracycline.......... .......... ......... .......... .......... .......... ......... ... 99
A n t i d i u r e t i c s . . . . . . . . . . . . .. . . . . . . . . . . . . . .. . . . . . . . . . . . . . . .. . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . .. . . 9 9 A n t i h i s t a m in in e s . . . . . . . . . . . . .. . . . . . . . . . . . . .. . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . 9 9 A n t i - A n x i et et y M e d i c a t i o n . . . . . . . . . . . . . .. . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 0 0 A r t h r i t i s M e d i c a t i o n s . . . . . . . . . . . . . . .. . . . . . . . . . . . . .. . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . .. . . . . 1 0 1 1.
H y d r o x y c h l o r o q ui n e S u l f a t e . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 0 1
A s t h m a M e d i c a t i o n .. .. . . . . . . . . . . . . .. . . . . . . . . . . . . . .. . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . 1 0 1 1.
Corticosteroids.............. .......... .......... ......... .......... .......... .. 101
B i r t h C o n t r o l . . . . . . . .. . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . .. . . . . . . . . . . . . .. . . . . . . . . . . . . . . . .. . . . . . 1 0 2 P a r k i n s o n ’ s D i s e a s e M e d i c a t i o n . . . . . . . . . . . . . .. . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . .. . . . . . 1 0 2
B l o o d P r e s su su r e M e d i c a t i o n . . . . . . . . .. . . . . . . . . . . . . .. . . . . . . . . . . . . . . . .. . . . . . . . . . . . . .. . . . . 1 0 2 B l o o d T h i n n i n g M e d i c a t i o n . . . . . . . . . . . . . . .. . . . . . . . . . . . . .. . . . . . . . . . . . . . . . .. . . . . . . . . . . . 1 0 3
C a n c e r M e d i c a t i on on . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 0 4 D e p r e s s io io n M e d i c a t i o n . . . . . . . .. . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . .. . . . . . . . . . . . . .. . . . . . . . . . 1 0 4 D i a b e t e s M e d i c a t i on on . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 0 6 D i l a t i n g E y e ( P u p i l s ) M e d i c i n e . . . .. .. . . . . . . . . . . . . .. . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . 1 0 6 E r e c t i l e D y s f u n c t i on on ( E D ) . . . . . . . . . . . . .. . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 0 7 H e a r t M e d i c a t i on on s . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 0 7 H i g h C h o l e s t e ro ro l M e d i c a t i o n . . . . . . . . . . . . .. . . . . . . . . . . . . . .. . . . . . . . . . . . . . . .. . . . . . . . . . . . 1 0 8 H o r m o n e R e p l a c e m en en t . . . . . . . . . . . . .. . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 0 8 I n f l a m m at at i o n . . . . . . . . . . . . . . .. . . . . . . . . . . . . .. . . . . . . . . . . . . . . . .. . . . . . . . . . . . . .. . . . . . . . . . . . . . . . 1 0 9 I n s o m n i a . . . . . . . . . . . . .. . . . . . . . . . . . . .. . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . .. . . . . . 1 0 9 M a l a r i a M e d i c a t i o n . . . . . . . . . . . . . .. . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . .. . . . . . . . . . . . . .. . . . . . . . 1 0 9 P a i n R e l i e f M e d i c a t i o n . . . . . .. . . . . . . . . . . . . .. . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . .. . . . . . . . . . . . 1 1 0 P s y c h i a t r i c M e d i c a t i o n . . . . . . . .. . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . .. . . . . . . . . . . . . .. . . . . . . . . . 1 1 0 S t e r o i d s . . . . . . . . . . . . . .. . . . . . . . . . . . . .. . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . .. . . . . . 1 1 1 V i t a m i n s . . . . . . . . . . . . . .. . . . . . . . . . . . . .. . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . .. . . . . . 1 1 2 W e i g h t L o s s . . . . . . . . . . . . . .. . . . . . . . . . . . . .. . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . .. 1 1 2 S e c t io i o n 2 T r e a ti t i ng n g D e fe f e c t iv iv e V i s i o n . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 1 3 C h a pt p t e r 6 : W e a ri r i ng n g G l as a s s e s: s : I s i t s a fe fe ? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 1 4
T h e O p t i c s o f E y e G l a s s e s . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . .. . . . . . . . . . . . . . . . .. . . . . . . . . . . . 1 1 5 M i n u s L e n s e s f o r R e a d i n g . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . .. . . . . . . . . . . . . .. . . . . 1 1 6 I m p o r t a n c e o f t h e O p t i c C e n t e r o f E y e G l a s s e s . . . . . . . . . . . . .. . . . . . . . . . . . . . .. . . . . 1 1 7 G l a s s e s a n d T h e i r E f f e c t s o n t h e S i z e o f E y e s . . . . . . . . . . . . . . .. . . . . . . . . . . . . . .. . . . . 1 1 8 G l a s s e s : A n n o y a n c e s a n d I n c o n v en en i e n c e . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 1 8 C h a pt pt e r 7 : L a s e r E y e S u r ge r y . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 1 9
T y p e s o f L a s e r E y e S u r g e r y . . . . . . . . . . . . .. . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . 1 2 0 L A S I K . . . . . . . . . . . . . .. . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . .. . . . . . . . . . . . . . .. . . . . . . . . . . . . . . .. . . . . . . . 1 2 0 P R K . . . . . . . . . . . . . .. . . . . . . . . . . . . . . .. . . . . . . . . . . . . . .. . . . . . . . . . . . . . . .. . . . . . . . . . . . . . .. . . . . . . . . . . 1 2 0 L A S E K . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . .. . . . . . . . . . . . . . .. . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . .. . . . . 1 2 0 R L E . . . . . . . . . . . . . .. . . . . . . . . . . . . . . .. . . . . . . . . . . . . . .. . . . . . . . . . . . . . . .. . . . . . . . . . . . . . .. . . . . . . . . . . 1 2 1 E p i L as as i k . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . .. . . . . . . . . . . . . . .. . . 1 2 1 P R E L EX EX . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . .. . . . . . . . . . . . . . .. . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . .. . . . . 1 2 1 I n t a cs cs . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . .. . . . . . . . . . . . . . .. . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . .. . . . . 1 2 1
P h a k i c I n t r a o c u l a r L e n s I m pl pl a n t s . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 2 1 A K . . . . . . . . . . .. . . . . . . . . . . . . . .. . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . .. . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . 1 2 2 R K . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . .. . . . . . . . . . . . . . .. . . . . . . . . . . . . . . .. . . . . . . . . . . . . . .. . . . . . . . . . . 1 2 2
S i d e E f f e c t s o f L a s e r S u r g e ry ry . . . . . . . . . . . . .. . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 2 2 Infections and Delays in Healing............ .......... .......... ......... ......... 122 U n d e r or o r O ve v e r C or or r e c t i o n . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 2 3 Worsening of Vision............ .......... ......... .......... .......... ......... ...... 123 Excessive Corneal Haze........ ......... .......... .......... .......... ......... ...... 123 Regression ......... .......... .......... ......... .......... .......... .......... ......... . 123 H a l os os . . . . . . . . . . . . . .. . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . .. . . . . . . . . . . . . . .. . . . . . . . . . . . . . . .. . . . . . . . 1 2 3 Damage or Loss of Flap......... .......... .......... .......... ......... .......... .... 124 S e c t io i o n 3 N a t ur u r a l W a y s t o I mp m p r o v e E y e s ig ig h t . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 2 5 C h a p t e r 8 : B a t e s ’ M e t h o d o f I m p r o vi n g E y e s i gh t . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 2 6
T h e B a t e s M e t h o d . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . .. . . . . . . . . . . . . .. . . . . . . . . . . . . 1 2 7 C o n v e n t i o na na l W a y o f T r e a t i n g V i s i o n . . . . . . . . . . . . . . .. . . . . . . . . . . . . .. . . . . . . . . . . . . . . . 1 2 8 B a t e s ’ T r e a t m e n t M e t h o d . . . . . . . . . . . . . .. . . . . . . . . . . . . . .. . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . 1 2 9
C i r c l e o f E y e S t r a i n . . . . . . . . . . . . .. . . . . . . . . . . . . .. . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . .. . . . . . . . . . 1 3 0 P r i n c i p l e s o f C l e a r V i s i o n . . . . . .. .. . . . . . . . . . . . . .. . . . . . . . . . . . . . . . .. . . . . . . . . . . . . .. . . . . . . . . . 1 3 1 1.
Central Fixation.......... .......... ......... .......... .......... ......... ...... 131
2.
Shifting .......... .......... ......... .......... .......... .......... .......... ..... 132
3.
Sunning .......... .......... ......... .......... .......... .......... .......... ..... 132
4.
Relaxation ......... ......... .......... .......... .......... ......... .......... .... 132
Chapter 9: Importance of a Healthy Diet
.. 133
N u t r i t i o n f o r t h e E y e s . .. .. . . . . . . . . . . . . .. . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 3 4 L u t e i n a n d Z e a x a n t hi hi n . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 3 4
I m p o r t a n t V i t a m i n a n d M i n e r a l s . . . . . . . . . . . . .. . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . .. . . . . . 1 3 5 V i t a mi mi n A . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . .. . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . 1 3 5 V i t a mi mi n C . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . .. . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . 1 3 6 V i t a mi mi n E . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . .. . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . 1 3 8 Z i n c .. . . . . . . . . . . . . . .. . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . .. . . . . . . . . . . . . . .. . . . . . . . . . . . . . . .. . . . . . . . 1 3 8 Beta-Carotene ......................................................................... 139 C h a pt pt e r 1 0 : E x e r c is e s f o r I m p r ov i n g V i s i o n . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 4 0
E x e r c i s e 1 – B r e a t h i n g . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 4 1 E x e r c i s e 2 – A f f i r ma m a t i o n s o f V i s i o n .. .. . . . . . . . . . . . . .. . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . 1 4 3 Present Affirmations......... .......... .......... ......... .......... .......... ....... 143 F u t u r e A f fi fi r m a t i o n s . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 4 3 N a t u r a l A f f i r ma ma t i o n s . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 4 4
E x e r c i s e 3 – P a l m i n g . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 4 5 E x e r c i s e 4 – F i g u r e E i g h t s . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 4 6 E x e r c i s e 5 – S c a n n i n g . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 4 7
Disclaimer
Copyright © 2014 - All Rights Reserved
N o p a r t o f t h i s p u b l i c a ti ti o n m a y b e r e p r o d u c e d i n a n y f o r m o r b y a n y m e a n s , including scanning, photocopying, or otherwise without the prior written permission of the copyright holder. The Author has strived to be as accurate and complete as possible in the creation of this book, notwithstanding the fact that he does not warrant or represent at any time that the contents within are accurate due to the rapidly changing nature of the subject. While all attempts have been made to verify information provided in this publication, the Author assumes no responsibility for e rrors, omissions, or contrary interpretation of the subject matter herein.
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Introduction Eyes are among one of the most complex yet fragile organs of our body. We often take this blessing for granted until we begin experiencing problems w i t h i t . T h e e y e s a r e n o t h i ng ng s h o r t o f b e i n g e x t r a o r d i n a r y . T h e y l e t u s perceive our surroundings in ways that cannot be conveyed in words. T h r o u g h o u r e y e s , w e e n j o y t h e c o l o r s o f l i f e – a f t e r a l l , s i g h t i s c o n s i d e r e d to be among the Five Senses of the human body. However, the capabilities of our eyes tend to decline with time . Such a decline sometimes occurs far quicker than you may have been exp ecting. A couple of eye tests follow where the optician tries to determine how much your vision has deteriorated. The next thing you know, you’ve been
p r e s c r i b e d a p a i r o f g l a s s e s o r c o n t a c t l e n s e s – a p p a r e n t l y i n a n a t t e m p t t o a s s i s t y o u r e y e s t o f u n c t i o n n o r m a l l y. y. T h e r e i s n o d o u b t t h a t y o u ’ l l s e e m u c h b e t t e r a n d c l e a re r w i t h a p a i r o f
glasses or contact lenses, but the truth behind them is far mor e daunting than people believe. Research has proven that these vision aids do not help i n i m p r o v i n g y o u r e y e s i g h t i n a n y w a y . T h i nk nk o f t h e m a s a n a i d d e s i g n e d t o h e l p y o u d e a l w i t h y o u r v i s i o n p r o b l e m s o n a t e m p o r a r y b a s i s – w h e r e a s t h e underlying problem lies as it is, and with time, may even get w orse as experienced by most people when their vision continues to get p oorer. This does not mean that glasses or contact lenses are of no use. On the contrary, without glasses, people with vision problems wouldn’t have been
able to lead their lives as normally as they do now. Neverthele ss, the whole point is, why not seek a more permanent solution? A solution that perhaps heals your eyes and improves your vision to an extent that you don’t need glasses any longer? In this book, we will begin by learning about how the human eye actually works, what factors determine vision and how they affect the pe rformance of your precious, delicate organ. We’ll then proceed to study the main reasons
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that lead to the decline in vision, along with the common types of problems related to the eye which are experienced by a lot of people. It is also important to know the particular types of drugs that are known to cause damage to the eye. The eye , no matter how valuable, is extremely delicate which makes it prone to harm from a v ariety of things. A clear u n d e r s t a n d i ng ng o f t h e s e t h i n g s i s v i t a l s o t h a t w e c a n c a r r y o u t t h e n e e d e d precautionary measures against such harm.
What is Vision? We have been used the w ord Vision several times, but do we really know what vision is? It is commonly used to imply things which we see. However, it is much more than that. A vision is an outlook on life. It is how you perceive the world around you. It encompasses more things than just eye sight. It is a wonderful blend of an i n d i v i d u a l ’s ’s i m a g i n a t i o n , t h e i r f e e l i n g s a n d t h o u g h t s r e g a r d i n g a n u m p t e e n
number of things. You may be wondering, what has this got to do with your eye sight? Well, it has everything to do with it. As we previously said, sight is o ne of the five senses humans are blessed with. As humans, we need inputs from all of our senses in order to comprehend, and to feel and propel ourselves towards a bright future. If even one of y our senses starts to give up on you, your awareness of the things around you will begin to change. Such is the importance of your eye sight. It is precious beyond any measure.
Healing the Eyes, Naturally Let us return to the core topic of this book; that is, the natural ways through which you can heal your eye sight and improve your vision. In this book, we’ll learn about a very interesting idea by a Professor of
O p h t h a l m o l og og y . A P r o f e s s o r c a l l e d W i l l i a m H o r a t i o B a t e s c a r r i e d o u t a
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detailed study of the use and effects glasses have on its wearer. He believed that almost all of vision problems were related to some kind of a habitual strain on the eyes. He even believed that wearing glasses had nothing but harmful effects, and that they are not necessary. Surprising, isn’t it? You must be growing more interested in Professor Bates’ research. However, it’s always a good idea to proceed through this book one
step at a time so that you are able to grasp all the important knowledge related to your eyes. The aim of this book is to empower you to lead a much more confident and pleasurable life, without your glasses. This book conveys vital knowledge in an interesting and logical way to help you make the right decision related to your eye sight.
How to Proceed Through the Book This book is carefully divided into three distinct se ctions. The first section deals with how the eye works, the common problems which a f f e c t i t , t h e i r s o l u t i o n s a n d c o n t a i n s i n f o rm a t i o n a b o u t d r u g s t h a t c a n h a r m the eye sight. The second section discusses the treatment methods for healing eye sight, including use of glasses and surgery. The third section talks about natural ways that can help you heal and protect your eyes from harm. This section includes useful information a bout a healthy diet, eye exercises and other things that can contribute to improving your vision.
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Section 1 – U N D E R S T A N D I N G V I S I O N
Chapter 1: How the Eye Works Chapter 2: Common Reasons for Eye stra in Chapter 3: Poor Eyesight: Facts and Misunderstandings Chapter 4: Types of Vision Problems and Their Solution Chapter 5: Drugs Harmful to the Eye
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Chapter 1 How the Eye Works The eye is extraordinary to say the least. Similar to the way our other senses of sound, taste, hearing
FACT: On average, people blink around 12 times a minute
and touch are connected to the human anatomy, the sight is also very closely interconnected to other parts of our anatomy - most importantly, the brain. Before we begin to discuss how the eye performs its functions and gives us vision, it is necessary to understand the anatomy of the eye it self. W h i l e a d e t a i l e d u n d e r s t a n d i ng ng o f t h e e y e i s n o t n e c e s s a r y t o b e a b l e t o i m p r o v e y o u r v i s i o n n a t u r a l ly ly , i t s u r e i s i n t e r e s t i n g t o l e a r n a b o u t h o w o u r delicate eyes work in order to be able to appreciate the delicate yet powerful organs.
Anatomy of the Eye
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Cornea C o r n e a i s a c l e a r c o v e r i n g w h i c h i s r e s p o n s i b l e f o r t r a n s m i t ti ti n g a n d f o c u s i n g the incoming light.
Fovea T h e F o v e a i s t h e c e n t e r o f m a c u l a a n d p r o v i d es es t h e s h a r p v i s i o n .
Iris Iris is the colored part of our eyes. It helps in regulating the amount of light t h a t e n t e r s t h e e y e . I n b r i g h t l i g h t c o n d i t i o ns , t h e i r i s c o n t r a c t s t h e p u p i l i n order to reduce t he incoming light. On the other hand, in low light conditions, the opposite happens and the iris causes the pupils to dilate to let in more light.
Lens T h e l e n s i s r e s p o n s i b le le f o r d i r e c t i n g t h e l i g h t o n t o
FACT: When compared to
the retina at the back of the eye. The lens is
all the other muscles in
transparent. Degradation in lens is common as we grow older. Cataracts are among one of the
your body, the muscles that control the eyes are the most active.
common eye problems, as we will learn in Chapter 3.
Macula Macula is the area found in the re tina which contains light sensitive cells. It is due to these cells that we are able to view the finest of details clearly at t h e c e n t e r o f o u r v i s u a l f i e l d . T h e m a c u la la d e t e r i o r a t e s w i t h a g e .
Optic Nerve The optic nerves consist of millions of nerve fibers that act a s a transport p a s s a g e – a l l o w i n g t r a n s m i s s i o n o f v i s u a l m e s s a g e s f r o m t h e r e t i n a t o t h e brain. These signals are then interpreted by the brain and it i s this interpretation that allows us to perceive things as they are.
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One of the most common problems of the eye includes Glaucoma that is related to optic nerves, which we will learn about in detail in Chapter 3.
Pupil Pupil is the darker opening in the center of the iris. We learned that the pupil alters its size in order to adjust the amount of light that enters the eye (see Iris ).
Retina FACT: The retina registers images as being upside down. It is the brain that
Retina is the nerve that lines the back of the eye. The incoming light is directed onto
turns the images the right
the retina which then generates electrical
side up.
impulses that are sent to the brain to be converted into images.
Working Principle of the Eye The whole working principle of the eye is based on the correct working of each of the various parts of the eye. In essence, the human eye works in remarkably similar ways to a digital camera. 1. The cornea focuses the incoming light, similar to the way the lens of a camera does. 2. The light focused by the cornea enters the iris, which acts similar to t h e d i a p h r a g m o f a c a m e r a – c o n t r o l l i n g t h e p u p i l ’ s t o d e t e r m i n e t h e correct amount of light reaches the back of the eye. 3 . T h e lens a u t o m a t i c a l l y a d j u s t s i n o r d e r t o f o c u s n e a r a n d a p p r o a c h i n g objects correctly, just like an auto-focus camera lens. 4. The light that is focused by the cornea and the lens (and contr olled by the pupil and iris) then hits the retina. The retina acts as an electronic image sensor of a camera by carrying out the conversion of optical i m a g e s i n t o e l e c t r i c a l s i g n a l s. s. 5. These electrical signals are then transmitted to the brain thro ugh the
optic nerves.
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6. The visual cortex (part of the brain that controls sight) then helps us to see.
Field of View of the Human Eye The field of view is simply the extent of the environment that can be see n at any given moment. The placement of the eyes determines the extent of the f i e l d o f v i e w . M a n y b i r d s a r e a b l e t o s e e 3 6 0 d e g r e e s – m e a n i n g t h e y a r e able to see who or what is at the front, the sides, and the back! For humans, the combined field of view is limited to ar ound 180 degrees. This explains why you can see from the ‘corner of your eye’ e ven when you
are focusing ahead of you. S e v e r a l e y e c o n d i t i o n s c a n r e s t r i c t a n d s i g n i f i c a n t l y d e g r a de t h i s f i e l d o f v i e w , t h e r e b y g r e a t l y l i m i t i n g a p e r s o n ’s a b i l i t y t o s e e .
Monocular Vision (orange
Binocular Vision (red area)
area) is the vision when each
is the vision when both eyes
eye is used on its own. This
are used simultaneously.
increases the field of view,
This decrease s the field of
but restricts the depth of
view, but increases the
perception
depth of perception
T h e d i f f e r e n c e b e t w e e n t h e t w o v i s i o n s d e t e r m i n e s t h e a b i l i t y t o c a l c u l a t e d i s t an an c e s
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Chapter 2 Common Reasons for Eye strain
Simply put, eye strain is a kind of discomfort in the eyes that occurs whenever our eyes tire after focusing on any particular task fo r an ex tended period of time. There is no doubt that eye strain can be extremely annoying and uncomfortable. However, it is not harmful in most cases and diminishes once the eyes are given some time to rest. N e v e r t h e l e s s , t h e p r o b a b i li li t y t h a t c e r t a i n s y m p t o m s o f e y e s t r a i n c a n indicate certain underlying eye problems cannot be ignored. This is why it is of an utmost importance that people understand the causes and effects of eye strain so that they can maximize their efforts to keep the eyes wellrested.
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Causes of Eye strain The causal factor that results in eye strain is health - the l ack of it, to be m o r e p r e c i s e . P o o r h e a l t h g o e s a l o n g w a y i n r e d u c i n g v i s i o n – a l o n g w i t h several other factors that are linked to a person’s lifestyle. This is why it is
vital that a person, who is experiencing from frequent eye strain issues, analyze his or her lifestyle to filter out any factors that may be behind the diminished vision. One of the things that would need to be analyzed is the type of life a person leads. The pace at which they lead t h e i r l i v e s – a h e c t i c , under pressure and a stressful life can s i g n i f i c a n tl tl y r e d u c e t h e strength of the eyes. It is often necessary to trace the steps back to the childhood of an i n d i v i d u a l. l. I t i s o f t e n a s a c h i l d t h a t w e a c q u i r e a n d d e v e l o p p o o r h a b i t s which in turn lead to the weakening of the eyesight. A lot of scientific evidence is available to prove the fact that infants and toddlers have brilliant eyesight, and this starts to deteriorate when a child begins to go to school. The question that comes up is, how can school contribute to a w eakening of eyesight? Well, the answer is simple enough: school puts a lot of p ressure on the students to learn and keep up with their peers. This pressure causes stress to build up in many of the pupils; and as we already know, stress is a factor that has detrimental effects on health, leading to eye strain. Some of the factors that contribute to eye strain are:
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F o c u s i n g t h e e y e s f o r e x t e n d e d p e r i o d s – F o c u s i n g o n a n o b j e c t f o r e x t e n d e d periods of time can result in e ye strain. Due to the very nature of the eyes, they are designed to shift their focus between near and remote objects ; this is why forcing them to focus on an object at close range persistently can tire them. P o o r o r i n a d e q u a t e l i g h t i n g – P o o r l i g h t i n g f o r c e s t h e e y e t o w o r k i n d i f f i c u l t conditions, thereby putting strain on the eyes. E x c e s s i v e G l a r e – G l a r e , r e g a r d l e s s o f w h e t h e r i t s d i r e c t o r i n d i r e c t , m a k e s c r e a t e s p r o b l e m f o r p r o p e r v i s i o n . A d i r e c t g l a r e o c c u r s w h e n a l i g h t – f r o m any type of light source- shines upon the eyes directly. Indirect glare, on the other hand, is the glare that it r eflected off computer screens.
Symptoms of Eye Strain Now that it’s clear as to what fa ctors cause eye strain. It is important to be
able to recognize the symptoms of e ye strain. The following symptoms can mean that a person is suffering from eye strain: 1. Burning or itching eyes FACT: Eyes are strained
2. Blurred/Double Vision
more easily when they are
3. Sore Eyes
focused on nearby objects
4. Sore Neck
for prolonged periods as
5. Frequent Headaches
compared to focusing on distant objects.
6. Shoulder Pain 7. A Heightened Sensitivity To Light
As it was previously said, the effects of eye strain do tend to vanish when t h e e y e s a r e a l l o w e d t o r e s t . N o n e t h e l e ss ss , r e p e a t e d s t r a i n i n g o f t h e e y e s w i l l ultimately result in weakening of the vision .
Preventing Eye strain Our daily lives are filled with stressful routines and the work that we do places enormous amounts of stress on our eyes. In today’s tech-savvy world
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where digital devices are found almost everywhere, it is extremely difficult to completely eliminate eye strain. However, certain preventiv e measures can be taken that would greatly reduce the chances of eye strain. Here are some ways to help you prevent eye strain:
1. Correcting Bad Habits
FACT: Bad habits usually
Most of the time, the cause of eye strain is not the particular thing that we do, but the way we do it. It
cause most of the damage t o a p e r s o n ’ s v i s i o n. n.
E l i m i n a ti ti n g b a d h a b i t s a n d
is vital that you break these bad habits and develop
replacing them with good
good ones to replace them.
ones can have a tremendous effect upon
A great number of people
vision.
possess the following bad habits:
R e a d i n g / W r i t i n g i n P o o r L i g h t i n g C o n d i t i o n s – While it is great to read yourself to sleep, reading in inadequate lighting conditions is among one of the most common bad habits that people acquire at a very young age.
S m o k i n g – M e d i c a l s c i e n c e h a s p r o v e d t h a t s m o k i n g severely damages the tissues in the eye; over 25 percent of cases of age-related macular degeneration were found to have links with smoking.
R e a d i n g W h i l e O n T h e M o v e – R e a d i n g w h i l e on the road makes the journey easy. Nonetheless, this makes i t difficult for the eyes to focus. Motion sickness may also kick in a n d l e a d t o h e a d a c h e s , d i z z i ne s s a n d v o m i t i n g .
S t a r i n g A t T h e S u n – S t a r i n g a t t h e s t a r s a t n i g h t i s a n o t h e r thing, but this shouldn’t be taken literally when it comes to looking up at our solar system’s giant fireball. A lot of people
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have a habit of directly looking up at the sun. Too much exposure can cause the macular in the eye to degenerate and cataracts to build up.
R u b b i n g I t c h y E y e s – R u b b i n g t h e e y e s c a n d a m a g e them. A cold compress is more suitable for t r e a t i n g a n y i r r i t a t i o n s – h o w e v e r , a v o i d a w a r m compress as it will only make the itching grow worse.
Breaking Bad Habits Breaking a bad habit is not as easy as it might s eem. This is why the f o l l o w i n g g u i d e l i ne s h a v e b e e n i n c l u d e d i n t h e b o o k t o h e l p y o u o v e r c o m e your bad habits once and for all.
1. Find a Good Habit to Replace Your Bad Habit
A bad habit cannot be simply eliminated; it has to be replaced by another habit in order to properly get rid of it. You will need to prepare a plan for yourself that will help you through the whole process.
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Firstly, decide which bad habit you will try to replace, and with what. For example, you may want to quit the habit of
FACT: Breaking a bad
reading in low-light conditions and replace it
habit is not an easy task.
with a good habit such as ensuring that whenever
However, it is not
you read, you do so in a well-lit area. Once you have defined goals and targets for
i m p o s s i bl bl e e i t h e r . W i t h a little determination, you can easily replace them with good ones.
yourself, the actual process would become much easier than you think.
Remove the Triggers Triggers do what their name implies; they trigger something. Anything. For example, you may have a habit of smoking whenever you go to the bar for a drink. In this case, going to the bar is the trigger that makes you smoke. The logical course of action in such a c ase would be to a v o i d g o i n g t o t h e b a r – a t l e a s t u n t i l y o u h a v e s o m e p o s i t i v e c o n t r o l on your smoking habit.
Surround Yourself With Motivation An important part of giving up a bad habit is to have r ole models around. This does not mean that you leave your current friends or social circle to enter a new one ; all it means is that you find some people who can help you with whatever you are trying to achieve .
Be Prepared For Failure Anyone can fail. What matters is that how an individual takes the failure. A failure can be a source of m otivation for the next time, as you’ll know why you failed, and you’ll avoid it the next time. To avoid
b e i n g d i s a p p o i n te d , p l a n f o r f a i l u r e s o t h a t y o u c a n c o n t i n u e p r o g r e s s i n g i n a d i f f e r e n t m a n n e r – i t ’ s a l l a b o u t m o v i n g f o r w a r d .
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2. Eliminate Glare
Glare is among the primary causes of eye strain. Certain measures should be t a k e n i n o r d e r t o r e d u c e o r c o m p l e t e l y e l i m i na t e g l a r e .
C o n t r o l t h e S o u r c e o f L i g h t – I t i s t h e d i r e c t l i g h t t h a t i s r e s p o n s i b l e f o r t h e greatest glare. Indoor lighting that is exposed FACT: Glare is a great contributor to eye strain.
can cause glare, try to have them enclosed in
E l i m i n a t i ng ng g l a r e i n d a y -
some form of a casing (such as shades or
to-day activities can
globes) so that you diffuse the light. Also,
protect your eyes from straining.
consider putting curtains or blinds on the windows to diffuse the incoming sunlight.
U s e t h e P r o p e r S u r f a c e – T h e s h i n i e r a n o b j e c t , t h e g r e a t e r t h e r e s u l t i n g glare. If your work desk has a tabletop made of glass, then it will create an enormous amount of glare and you will have eye strain much quicker. Cover
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t h e t a b l e w i t h , s a y , a f a b r i c t o e l i m i n a t e t h i s i s s u e. e. S a m e g o e s w i t h c o m p u t e r monitors; put a glare filter over them to reduce the amount of glare. It is also recommended that you put your work surface at an angle of approximately 90 degrees from the light source in order to redu ce the glare and reflections.
P r o t e c t i n g Y o u r E y e s O u t d o o r s – Y o u c a n n o t h a v e t h e l u x u r y o f c u r t a i n s a n d blinds while you wander outdoors. The best way to protect the e yes from g l a r e i s t o w e a r p o l a r i z e d s u n g la s s e s t h a t a r e d e s i g n e d f o r t h i s v e r y p u r p o s e . Such types of glasses are ideal for driving as sunlight will ge t reflected a lot from vehicles around you.
3. Reduce the Contrast Reducing the contrast is another way to greatly reduce the glare. Today’s high contrast displays no doubt make the images look sharp and beautiful, but they aren’t necessarily good for the eyes. Whenever you use a computer
or a tablet, do try turning down the contrast to levels that you feel are easy on your eyes. Among one of the m ost eye-straining combinations is reading b l a c k t e x t o n a b r i g h t w h i t e b a c k g r o u n d. d.
4. Toughen Your Eyes While it is great to be able to control external factors which affect the eye, but you should also pay great attention to strengthening your o wn eyes. One o f t h e g r e a t e s t w a y s t o n a t u r a l ly ly i m p r o v e e y e s i g h t i s b y e x e r c i s i n g y o u r e y e s . A number of exercises can be found in Chapter 10
20-20 Rule For every twenty minutes spent focusing on any particular work, a break
of this book.
5. Rest Your Eyes Working for prolonged periods of time imposes a
should be taken where
great amount of strain on our eyes. It is
you should look at
u n d e r s t a n d a b le le t h a t e x t e n d e d b r e a k s a r e n o t
something that is placed twenty feet away for twenty seconds..
possible all the time. This is why the 20-20 rule s h o u l d b e a p p l i e d w h e n e v e r p o s s i b le le . A c c o r d i n g
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to the 20-20 rule, for every twenty minutes spent
FACT: It is interesting to
focusing on any particular work, a break should be
know that only 20 percent
taken where you should look at something that is placed twenty feet away for twenty seconds.
of an eye’s focusing power
is due to the lens; the rest comes from the
6. Focus from a Distance Our eyes work more effectively when we focus at distance object s. Prolonging our focus on nearby objects can cause e ye strain. Whenever working with objects that are close to your field of view, it is vital that you take regular breaks in between to avoid straining your eyes.
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Chapter 3 Poor Eyesight: Facts and Misunderstandings
Our eye sight tends to deteriorate with time due to several factors. Some of deterioration is from natural causes, that is, due to aging. While some are the direct result of the way we live our lives (lifestyle). Lifestyle, or the way we live our lives, is an extremely broad topic when it comes to discussing its effects on the eyes. Up till now, we have discussed some of our bad habits and a few of the factors pertaining to the environment (glare). Our diet is yet another important factor in determining the hea lth of our eyes, and we will be discussing nutrition in detail in Chapter 9 of this book. There are also specific drugs which tend to have side effects s trong enough t o h a r m o u r e y e s . T h e s e d r u g s w i l l a l s o b e d i s c u s se d i n d e t a i l i n t h e n e x t chapter.
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The purpose of this chapter is to empower you with some facts about poor e y e s i g h t , a s w e l l a s c l e a r u p s o m e o f t h e m i s u n d e r s t an an d i n g s t h a t a r e widespread among people. There are a lot of things that we have been believing in for years, and perhaps in some cases, since childhood. It is of an u t m o s t i m p o r t a n c e t o d i s m i s s t h e s e m i s u n d e r s t a n d i ng s s o t h a t a c l e a r u n d e r s t a n d i ng ng o f w h a t i s g o o d a n d w h a t i s n o t g o o d f o r o u r e y e s i g h t c a n b e gained. Let us proceed through this chapter by talking about, and clearing the common myths.
Myths Myth Number 1: Not using glasses will damage the eyes This is not entirely true. On the contrary, research has shown that using glasses can actually further deteri orate vision rather than healing it. Our eyes can heal themselves naturally provided that they are given the proper a t t e n t i o n a n d c a r e . A c o m b i n a t io io n o f e y e e x e r c i s e s , p r o p e r n u t r i t i o n a l i n t a k e as well as common sense can go a long way in naturally healing vision problems.
Myth Number 2: Reading in Dim Light Damages the Eyes This is yet another myth. Reading in dim lighting conditions in no way damages your eyes; however, it can strain your eyes. This is th e reason why i t i s r e c o m m e n d e d n o t t o r e a d i n p o o r l i g h t i n g c o n d i t i o ns .
Myth Number 3: Consumption of Carrots Can Heal Vision Carrots are a rich source of Vitamin A, and vitamin A is indeed a requirement of our eyes. However, it is commonly believed that eating lots of carrots can i m p r o v e t h e e y e s i g h t – t h i s i s n ’ t t r u e , b e c a u s e t h e q u a n t i t y o f v i t a m i n A t h a t i s r e q u i r e d i s v e r y l i t t l e , a n d i t c a n b e a b s o r b e d b y c o n s u mi n g a h e a l t h y d i e t in general.
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Myth Number 4: Nothing Can Be Done To Prevent Loss of Sight This is among one of the most discouraging statements that are circulated around. Our eyes are a set of w onderfully crafted organs, and given the time a n d c a r e , t h e y c a n h e a l t h e m s e l v e s . R e g u l a r e y e e x a m i n a t i o n s s h o ul ul d b e scheduled to keep a track on the eyes’ health.
Natural ways of healing include consuming a healthy, balanced diet and performing numerous exercises.
Myth Number 5: Eye Examinations Are Only Necessary When Experiencing Problems The whole purpose of eye examinations is to ensure that the eyes are f u n c t i o n i n g p r o p e r l y w i t h o u t a n y p r o b l e m s . A n e x a m i n a t i on on b r i n g s t o l i g h t any lingering problems before they actually set in. An examination may also reveal any serious conditions that may not be showing any obvious symptoms. T h a t b e e n s a i d , e y e e x a m i n a t i o ns ns s h o u l d n e v e r b e m i s s e d a n d m u s t b e a p a r t of your health care regime.
Myth Number 6: Using a Computer for Extended Periods Can Damage th e Eyes Computer screens do emit harmful rays at all. X -Rays and Ultraviolet rays are known to damage the eyes, and these types of rays are not emitted by computer screens. A l o t o f p e o p l e t e n d t o c o n f u s e e y e s t r a i n w i t h e y e d a m a g e – y e s , m o n i t o r s can cause eye strain if they are used for extended periods of time with no b r e a k s i n b e t w e e n – b u t n o , t h e y c a n n o t d a m a g e y o u r e y e s .
Myth Number 7: Sitting Too Clo se to a Television Can Damage Children’s Eyes
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There is no evidence at all that could prove this statement to be true. On the contrary, children can focus at closer objects much better than adults can. It is also observed that children tend to read books by holding them close to their eyes. This habit tends to go away with age, but if a child frequently sits c l o s e t o a t e l e v i s i o n – t h e n t h e y s h o u l d u n d e r g o a n e y e e x a m i n a t i o n t o c h e c k w h e t h e r o r n o t t h e y a r e s u f f e r i n g f r o m m y o pi pi a , o r s h o r t s i g h t e d n e s s .
Myth Number 8: People with Weak Vision Should Avoid Focusing on Intricate Details It is also commonly believed that focusing on fine details can further deteriorate the vision further, especially in people who already have weak eyesight. This concept is based on the idea that an eye is a muscle, and using it will wear it out. A better and more accurate comparison of the eye is that to a camera. A c a m e r a d o e s n o t w e a r o u t i f i t i s u s e d t o t a k e p i c t u r e s o f v e r y f i n e d e t a i l s – same is the true with our eyes.
M y t h N u m b e r 9 : E y e s c a n b e T r a n s p l an an t e d T h i s i s n o t t r u e . N o m a t t e r h o w a d v a n c e d m e d i c a l s c i e n c e b e c o m e s , t hi s i s something that will remain impossible. The eyes are connected to the brain t h r o u g h t h e o p t i c n e r v e – w h i c h i s a c o l l e c t i o n o f m i l l i o n s o f n e r v e s . O n c e t h e o p t i c n e r v e i s s e v e r e d , t h e r e i s n o w a y o f c o n n e c t i n g t h es e b a c k t o g e t h e r again. This is why during surgery; the eyes are never taken out of the socket. On the other hand, the cornea in the eye has undergone numerous t r a n s p l a n t a t i on on s o v e r t h e y e a r s . P e o p l e t e n d t o c o n f u s e t h i s c o r n e a l t r a n s p l a n t w i t h a n e y e t r a n s p l a n t. t. C o r n e a l t r a n s p l a n t i s p o s s i b l e ; e y e transplant is not.
Myth Number 10: Wearing Contact Lenses Prevents Nearsightedness fr om Worsening
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Contact lenses, similar to glasses, are not a permanent solution to eye sight problems. They only provide a temporary method to cor rect vision and they a r e n o t a b l e t o h e a l o r i m p r o v e v i s i o n c o n d i ti o n s i n a n y w a y . O n t h e contrary, wearing contact lens exposes the user to many risks as follows: o
They can cause dryness of the eyes
o
They can result in corneal scratches
o
They can cause corneal infections
o
They can cause the shape of the cornea to change
o
They can cause eye inflammation
o
They can cause eyelid inflammation
o
The lens solutions can result in an allergic reaction
Facts
Problems related to the eye and vision are regarded as being the second most common health care issue in the US. Some sort of v ision problems are known to affect more than 120 million people all across the country.
It is estimated that around 61 percent of the American population needs some form of correction for proper vision. This percentage accounts for around 172 million people. H owever, majority of these people are not aware of the fa ct that they can greatly enhance their eyesight without the need of going through a surgery or without wearing glasses or contact lenses.
Those people who repeatedly go to an optician with the same complaints of not being able to see clearly enough are not aware that wearing glasses will have hardly, if any, effect on improving their v i s i o n . G l a s s e s a c t u a ll y c a u s e t h e i r v i s i o n t o g e t w o r s e d a y b y d a y .
Common complaints are about children not being able to see the b o a r d s a t s c h o o l , m a n y t e e n a g e r s ’ i n a b i l i t y t o c l e a r l y s e e s t r e e t s i g n s –
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causing them to fail driver license’s tests. The solution that is provided, with the corrective devices increasing in power, rarely solve the problem!
One out of four of American children aged between 3 a nd 16 wear glasses to correct their vision.
Around 75 percent of people who frequently use a computer (at work, on daily basis), suffer from some sort of a vision problem; the symptoms could range from headaches, dry eyes, or blurred visio n and irritation in the eyes as a result of excessive eye s train.
Among one of the most common types of self-reported vision problems a r e c a t a r a c t s . I t i s a l s o t h e t h i r d l e a d i ng ng c a u s e o f b l i n d n e s s t h a t c o u l d have been prevented.
If you remember the time you got your first pair of glasses, you would have been told to wear them until you got used to them. Sounds familiar? Well, once you got used to them and you took them off, everything would seem blurry and cause you to become dizzy. I f you remember more precisely, things would be far blurrier than they were before you started wearing the glasses. Why? There’s only one logical explanation for all of this. By using stronger
p r e s c r i p t i o n s e a c h t i m e , w e h a v e o n l y b e e n c a u s i n g o u r v i s i o n t o d e t e r i o r a t e. The human body has been designed in a way that it has the abili ty to heal itself and regenerate, given the time. There is no doubt that modern medical s c i e n c e h a s m a d e e x c e p t i o n al al a d v a n c e m e n t s a n d h a s i n t r o d u c e d t h i n g s t h a t improve healing ability of the body. Nevertheless, there are some things that need time and nothing can accelerate the m. Similarly, our eyes can heal and regenerate if given the time without any additional aid such as glasses or contact lenses.
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The eyesight is unarguably the most vital sensory channel that humans are blessed with; over 90 percent of all the information that the brain receives from varying senses is a ctually from the eyes. Through this sensory input, the brain figures out when to react to what we see. Our movements, our speech and conversations with other people as well as gestures all are result of the interpretation of the electrical signals executed by the eye. All the body’s systems are in fact interlinked in one way or another.
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Chapter 4 Types of Vision Problems and Their Solutions In a manner similar to other parts of our body, the eyes tend to deteriorate w i t h a g e . A p r o b l e m w i t h t h e e y e s i g h t i s n o s m a l l p r o b l e m a t a l l – b y r e a d i n g through the previous chapters of this book, you would have developed a clear picture of how important vision is for humans. Nevertheless, as important as it is, it is also fragile and can experience many disorders that may not be particularly related to aging. I n t h i s c h a p t e r , w e w i l l d i s c u s s s e v e r a l t y p e s o f v i s i o n p r o b l e m s i n d e t a il a n d talk about the factors that cause these problems to occur in the first pl ace. We will then move on to discuss the possible solutions for these vision problems in order to help improve vision acuity. B e f o r e w e g e t i n t o t h e d e p t h s o f l e a r n i n g a b o u t v i s i o n p r o bl e m s , i t i s necessary that you first have a standard set that can act as a reference to which you can compare. This standard is a healthy eye, and as we know, the body’s sensory and processing systems work in conjunction, i.e. eyes and
b r a i n t r a n s f e r i n f o r m a t i o n t h r o ug ug h t h e o p t i c n e r v e s . F o r a h e a l t h y e y e t o operate at peak efficiency, it is vital that all the other related systems of the body are also working in harmony. That been said, vision involves not only the eyes, but the brain and all that connects them: For a healthy vision, a pair of healthy eyes with each of the ey e’s components working perfectly is required. For a healthy vision, a healthy brain that is capable of correctly interpreting the signals sent to it by the eyes is required.
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Apparently, by leading a healthy lifestyle that consists of an adequate diet, regular exercise and good habits does an excellent job of keeping the whole body in perfect shape. The complex interaction between the brain and eyes is a sensitive one; and p r o p e r c o n t r o l o f t h e m i n d i s o f a n u t m o s t im p o r t a n c e w h e n i t c o m e s t o a li t i e s . T h e m i n d c a n h a v e p o w e r f u l e f f e c t s o n t h e r e s t b o d y ’ s s e l f - h e a l i n g a b i li o f t h e b o d y – t h e m i n d c a n e i t h e r a s s i s t i n h e a l i n g , o r i t c a n b e c o m e a hindrance on the road to self-healing. Let us recall the main purpose of this book: which is to help y ou to restore y o u r v i s i o n n a t u r a l l y – – t h i s m e a n s t h a t y o u w i l l b e u s i n g y o u r b o d y ’ s o w n healing properties to encourage healing of your vision. To achieve this, you w i l l n e e d t o h a v e t h e r i g h t m i n d s e t – a m i n d s e t t h a t i s w i l l i n g t o a s s i s t t h e body in achieving the set goals and targets; only then you will have the capacity to benefit from this guide.
Loss and Impairment of Vision Most of the people experience various vision problems at some point in their l i v e s . S o m e p e o p l e h a v e d i f f i c u l t y f o c u si n g o n f a r - o f f o b j e c t s , w h i l e s o m e have problems in viewing things that are closer to them. Some also suffer from blurry vision. All in all, one vision problem or the other can severely affect the quality of life a person leads. These problems can c reate a hindrance in performing even the simplest of daily tasks, such as reading newspapers, browsing the internet or even recognizing people can be difficult. By definition, Visual impairment is defined as being any kind of a loss of vision that causes someone to some of their eyesight, or in some cases, make them completely go blind. Visually impaired people have vision problems even with assistive aids. On the other hand, Loss of Vision is a much broader term that generally implies a loss of vision that may have occurred abruptly, or sl owly over time.
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What Causes Vision Loss? There can be a number of r easons that can cause l oss of vision. Loss of vision can occur at any age for a number of reasons, but in most of the c a s e s , a g e i s a m a j o r f a c t o r – t h e e y e s b e g i n t o d e t e r i o r a t e w i t h a g e w h i c h i n turn causes some form of vision loss to kick in. Usually, vision loss does not occur in children, unless or unti l they have had an accident in which the eye was damaged in some way , or it could also occur if they have a really unhealthy lifestyle. S o m e b a b i e s a r e b o r n w i t h a c o n d i t i o n c a l l e d c o n g e n it it a l b l i n d n e s s , w h i c h means that they are visually impaired at birth. This could be d ue to a number of reasons:
C o n g e n i t a l B l i n d n e s s c a n b e i n h e r i t e d – i f t h i s c o n d i t i o n p r e v a i l s i n either of the parents, then there are chances that the baby will be born with it.
C o n g e n i t a l B l i n d n e s s c a n b e c a u s e d b y s o m e i n f e c t i o n – T h i s c o n d i t i o n can also be transmitted onto the baby as a result of an i nfection. If the mother was infected (with something like the German measles) then the developing fetus could contract it.
Level of Visual Im pairment In the United States, the f ollowing four terms are used to describe a student’s visual impairment in order to help them accordingly:
P a r t i a l l y S i g h t e d – s t u d e n t s w h o a r e c a t e g o r i z e d a s b e i n g p a r t i a l l y sighted usually require a person who is able to provide them with
special education
L o w V i s i o n – L o w v i s i o n r e f e r s t o a m o r e s e v e r e v i s u a l i m p a i r m e n t . T h i s t e r m a p p l i e s t o a l l t h o s e i n d i v i d u a ls w h o a r e u n a b l e t o r e a d a newspaper from a normal reading distance.
L e g a l l y B l i n d – T h i s i m p l i e s t h a t a p e r s o n h a s a v i s i o n t h a t i s l e s s t h a n 20/200 after use of corrective aids.
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T o t a l l y B l i n d – s t u d e n t s w h o a r e t o t a l l y b l i n d a r e p r o v i d e d w i t h B r a i l l e or other non-visual study materials to learn.
However, a visual impairment does not necessarily has to be this severe, numerous conditions that we will talk abo ut also result in temporary visual impairment of some kind that can be healed if proper measures a re taken. T h e r e a r e , o f c o u r s e , o t h e r v i s i o n p r o bl bl e m s t h a t m a y d e v e l o p a f t e r b i r t h a t any point during a person’s life. Some of those problems which we will
discuss in detail are as follows.
Visual Disturbances A number of vision problems can occur that can cause one or m ore of the following visual disturbances:
1. Diplopia 2. Halo 3. Blurred Vision 4. Color Blindness 5. Total Blindness 6. Eye Pain R e g a r d l e s s o f t h e t y p e , a n y s y m p t o m s o f v i s i o n l o s s a r e u n d o u bt e d l y a g r e a t cause of apprehension. Some of the underlying factors that may have lead to t h e v i s i o n l o s s c a n b e e x t r e m e l y s e v e r e m e d i c a l c o n d i t i o ns ns . I n s o m e c a s e s , any changes in the vision of a person can be classified a s a medical emergency as it could lead to a complete loss of sight, or even death. Even if the loss of vision is temporary, it still should not be taken lightly at all. The culprit behind temporary loss of vision can be from on e of the following serious medical conditions:
Stroke
Hypertension
Epilepsy
Migraine
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Transient Ischemic Attack (TIA)
1. Diplopia
Diplopia, or double vision, is a symptom that must be taken very seriously. While some of the causes of double vision may be negligible, some of the causes necessitate that immediate medical attention be provided.
Causes of Double Vision (Diplopia) A lot of people take their vision for granted; until one day they open their eyes and fail to see a single, lucid
Figure 1: A person with diplopia has double vision
image they used to see with their perfect vision. Let us quickly recap on the different areas of the vision system before we p r o c e e d w i t h d i s c u s s i n g t h e c a u s e s o f d o u b l e v i s i o n.
Cornea - The cornea is a clear window that lets light into the eye. I t is responsible for focusing the incoming light onto the appropriat e parts of the eye.
L e n s – T h e l e n s i s s i t u a t e d b e h i n d t h e p u p i l a n d i t a l s o h e l p s i n focusing the incoming light onto the retina.
E x t r a o c u l a r M u s c l e s ( m u s c l e s o f t h e e y e ) – T h e e x t r a o c u l a r m u s c l e s a r e r e s p o n s i b l e f o r r o t a t i n g t h e e y e – t h i s i s p r e c i s e l y w h a t l e t s u s move our eyeballs.
N e r v e s – I t i s t h e n e r v e s t h a t t r a n s p o r t a l l o f t h e v i s u a l i n f o r m a t i o n t o t h e b r a i n f o r p r o c e s s i ng ng .
bl e f o r B r a i n – T h e b r a i n h a s d e d i c a t e d a r e a s t h a t a r e r e s p o n s i bl p r o c e s s i n g t h e i n c o m i n g v i s u a l i n f o r m a t io n f r o m t h e e y e .
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As long as these systems work in harmony and continue to functi on as they a r e s u p p o s e d t o – n o v i s i o n p r o b l e m s a r e e n c o u n t e r e d . H o w e v e r , a s s o o n a s e v e n a s i n g l e p a r t b e g i n s t o m a l f u n c t i o n i n a n y w a y – t h e p r o b l e m o f d o u b l e vision can be experienced by a person.
C o r n e a P r o b l e m s – C e r t a i n p r o b l e m s w i t h t h e c o r n e a c a n l e a d t o d o u b l e vision. Any such problems in the cornea usually cause double vision in a single eye only. If a pe rson covers that specific eye, the double vision p r o b l e m t e n d s t o g o a w a y . I t i s d u e t o t h e a b n o r m a l s u r f a c e ( c o r n e a) a) t h a t twists the incoming light in a way that results in double vision. This abnormality can happen due to the following reasons:
Any infections in the cornea of the eye, including herpes zoster or shingles
Corneal Scars can create unequal visual images
Dryness of cornea also causes double vision
L e n s P r o b l e m s – A m o n g l e n s p r o b l e m s , c a t a r a c t s a r e o n e o f t h e m o s t common problems that can lead to double vision. If the cataract develops in both the eyes, then both eyes will create inaccurate images. More information about cataracts will follow in this chapter.
M u s c l e P r o b l e m s – W e a k e n i n g o f t h e m u s c l e s c a n h i n d e r t h e s m o o t h movement of the eye. If a person gazes in the direction of the weak muscle, they may experience double vision. Muscle problems can result from the following: -
ne s y s t e m t h a t M y a s t h e n i a G r a v i s : T h i s i s a n i l l n e s s o f t h e a u t o i m m u ne tends to block the stimulation of muscles by the nerves that ar e p r e s e n t i n s i d e t h e h e a d o f a p e r s o n . S i g n s o f m y a s t h e n ia ia g r a v i s a r e drooping eyelids and double vision.
-
G r a v e s ’ d i s e a s e : T h i s i s a t h y r o i d c o n d i ti o n t h a t h a s c e r t a i n e f f e c t s o n
t h e e y e m u s c l e s . T h i s d i s e a s e i s c o m m o n l y k n o w n t o c a u s e d i p l o p ia ia i n
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t h e v e r t i c a l p l a n e – t h e r e b y c a u s i n g o n e i m a g e t o b e s u p e r i m p o s e d o n top of another. bl e f o r c a r r y i n g t h e v i s u a l N e r v e P r o b l e m s – T h e n e r v e s t h a t a r e r e s p o n s i bl i n f o r m a t i o n t o t h e b r a i n f o r p r o c e s s i ng ng c a n a l s o b e c o m e d a m a g e d f o r n u m b e r of reasons. These nerves not only carry the message, but some o f these control the muscle movements. The following problems can affect the nerves: -
Multiple Sclerosis: is a problem that affects the brain and the spinal cord. This can affect the nerves anywhere around these two areas. If any of the nerves that control the eyes are damaged, double vision can occur.
-
Gullain-Barre Syndrome: This is a condition that progressively weakens the nerves and one of the first symptoms that may show in the eye is double vision.
-
D i a b e t e s : D i a b e t e s i s a m o n g o n e o f t h e m a j o r c u l p r i t s r e s p o n si b l e f o r damaging nerves near the eyes. It can damage the muscles that are responsible for controlling the eye muscles, thereby causing do uble vision.
te d B r a i n P r o b l e m s – S o m e o f t h e f a c t o r s t h a t c a u s e d o u b l e v i s i o n a r e o r i g i n a te from the brain itself. Any of the following in the brain can result in double vision, because the brain is the ultimate visual processing unit: -
Aneurysms
-
Increased blood pressure
-
Brain Tumor
-
Migraine
-
Strokes
Types of Diplopia There are mainly two types of diplopia:
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M o n o c u l a r D i p l o p i a i s s a i d t o o c c u r w h e n o n l y o n e e y e e x p e r i e n c e s d o u bl e vision. This is usually a result of abnormal surface in the af fected eye.
B i n o c u l a r D i p l o p i a i s s a i d t o o c c u r w h e n d o u b l e v i s i o n i s e x p e r i e n ce d i n b o t h t h e e y e s . T h i s u s u a l l y r e s u l t s i f t h e e y e s a r e p o o rl y a l i g n e d o r a n y k i n d o f nerve damage has occurred.
2. Halo Vision
A person is said to experience halo vision when halos appear as circles of light around the objects a person views. To be more precise, a medical dictionary describes Halo vision as “a condition in which colored or luminous rings are seen around lights.”
Causes of Halo Vision Halo vision can be caused by the following eye disorders: Figure 2: Halos appear around lights
Corneal Endothelial Dystrophy
Cataract
Glaucoma
The above conditions will be discussed in more detail later on in this chapter.
3. Blurred Vision Blurred vision is caused by loss of sharpness in the eyesight o f a person. It makes objects appear hazy and out of focus. Blurry vision can be a prime indicator of any underlying eye diseases. Regardless of whether i t occurs occasionally or on a regular basis, it should not be left untre at ed. People with blurred vision will have problems in viewing the finer details of a scene while the lack of focus can really frustrate them.
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Types of Blurred Vision S i m i l a r t o d i p l o p i a , b l u r r e d v i s i on c a n o c c u r i n e i t h e r o n e o r b o t h o f t h e eyes. When it occurs in a single eye, it is termed as unilateral blurred vision , and when it occurs in both, bilateral blurred vision.
Symptoms of Blurred Vision In certain cases, blurred vision may be accompanied by several of the following symptoms, apart from the problems of lack of focus and haziness:
Figure 3: A person who has blurred vision will see something like this when looking at a person standing in front of them. The level of blurriness will depend on the severity of the case.
P h o t o p h o b i a – S e n s i t i v i t y t o l i g h t
Spots or Floaters
Pain in the Eye
Any Discharge from the Eyes
Loss of Peripheral Vision
Loss of Central Vision
Eyes becoming Dry
Itchy Eyes
Night Vision Problems
Bloodshot Eyes (red)
Causes of Blurred Vision A s s t a t e d a b o v e , b l u r r e d v i s i o n c a n b e a n i n d i c a t i o n o f a s e r i o u s u n d e r l y i ng ng problem. It is obvious that people who wear glasses experience blurred vision when they take the glasses off. However, the actual problem arises when blurred vision occurs with corrective measures in place. Blurred vision can occur due to the following:
Myopia
Hyperopia
Presbyopia
Astigmatism
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Glaucoma
Macular Degeneration
Cataracts
Migraines
Dry Eyes
The above eye disorders will be discussed in more detail further ahead in this chapter. Other factors that may cause blurry vision include pregnancy. During pregnancy, it is common to experience blurred vision. Double vision (diplopia) may also accompany blurry vision as a result of the hormonal changes that are known to change the thi ckness and shape of the cornea. Dry e y e s – w h i c h c a n c a u s e b l u r r e d v i s i o n – a l s o o c c u r f r e q u e n t l y i n p r e g n a n t women, and can thereby play its part to lead to a blurred vision.
4. Color Blindness It is estimated that color blindness affects around 1 in 12 men around the world; women are less affected with 1 in every 200 being color blind. Color Blindness is known as color vision deficiency. Color blind people
usually see as clearly as other people who have normal vision; however, they have problems in seeing red, green or blue light.
Types of Color Blindness Retina is the part of the eye that senses light and controls color
Figure 4: An example of how a color blind person may interpret different colors.
vision. The retina is composed of two unique types of structures,
and they are:
R o d s – T h e r o d s a r e d e s i g n e d t o h e l p u s s e e i n l o w l i g h t c o n d i t i o n s
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C o n e s – T h e c o n e s a r e d e s i g n e d t o h e l p u s s e e c o l o r
Both the rods and cones have photosensitive chemicals in them. Rhodopsin is found in the rods; and photopigments are in the cones. The cones themselves are divided into three types w i t h e a c h c o n e i n c o r p o r a t i ng ng a d i f f e r e n t photopigment that is sensitive to a specific light
FACT: In the late 1700s, John Dalton was an English chemist,
(based on the w avelength). Most of the people
meteorologist and a
who have normal vision (called trichromatic) are
physicist. He was color
blessed with all of the three types of cones.
blind and he had requested that his eyes be
The term colorblindness is actually quite ambiguous as it implies that a colorblind person
examined after his death. He thought his eyes were tinted blue and that
sees everything in black and white. This is why we
caused him to see
will use the term color vision deficiency as it
differently from other
h e l p s i n d e s c r i b i ng ng t h i s v i s i o n c o n d i t i o n m o r e accurately. Simply put, it is the defect in any of those three cones that causes a person to
people around him. Deuteranopia is also known as Daltonism.
experience CVD. The three types of cones with their unique photopigments (red, green, blu e) are present in normal human vision; however, any defect in any of the three cones will upset the balance of color.
Defects in the Three Cones Those people who have slight defects in their color vision are said to have a n o m a l o u s t r i c h o m ac a c y , m e a n i n g t h a t t h e y h a v e a l l t h r e e t y p e s o f t h e c o n e s ,
but one of their cones is faulty. A n o m a l o u s t r i c h o m a c y c a n b e f u r t h e r d i v i d e d i n t o t h r e e t y p e s o f a n o m a l i e s : o
D e u t r a n o m a l y – – d e f e c t i n t h e r e d c o n e s
o
P r o t a n o m a l y – d e f e c t i n t h e g r e e n c o n e s
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o
T r i t a n o m a l y – u s u a l l y q u i t e r a r e – p e o p l e w i t h t h e s e t y p e s o f
anomalous trichomacy have problems in distinguishing between yel low and blue colors.
Missing Cone Color Vision Deficiency does not occur only because of a defective cone, but also because of an absence of one. An absence of a cone is more severe than anomalous trichromacy. T h o s e p e o p l e w h o h a v e a m i s s i n g c o n e a r e s a i d t o h a v e d i c h r o ma ma t i c v i s i o n , a n d i t c a n b e d i v i d e d i n t o t h e f o l l o wi wi n g : o
D e u t e r a n o p i a – i s t h e a b s e n c e o f g r e e n c o n e s . T h e g r e e n c o n e s a r e also commonly referred to as the L cones, due to their sensitivity to longer wavelengths of light.
o
P r o t a n o p i a – i s t h e a b s e n c e o f r e d c o n e s . T h e r e d c o n e s a r e a l s o c o m m o n l y r e f e r r e d t o a s t h e M c o n e s , d u e t o t h e i r s e n s i t i v i ty ty t o medium wavelengths of light.
o
T r i t a n o p i a – i s t h e a b s e n c e o f b l u e c o n e s . T h e b l u e c o n e s a r e a l s o commonly referred to as the S cones, due to their sensitivity to shorter wavelengths of light.
Black and White Monochromacy is a type of color blindness in which people see everything as black and white with s hades of gray in between. Monochromacy can also be divided into two types: o
A c h r o m a t o p s i a – T h i s i s a l s o k n o w n a s r o d m o n o c h r o m a c y a n d p e o p l e suffering from this also have an e xtremely poor vision as well as high l e v e l s o f p h o t o s e n s i ti ti v i t y ( s e n s i t i v i t y t o l i g h t ) . N y s t a g m u s a l s o accompanies this making their eyeballs look unsteady.
o
C o n e m o n o c h r o m a c y – T h i s t y p e o f m o n o c h r o m a c y i s q u i t e r a r e , however it does not deteriorate the vision.
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Monochromacy renders a person unable to distinguish between any colors w h a t s o e v e r . T h i s h a s t h e m f a c i n g a l o t o f p r o b l e m s i n e v e r y d a y a c t i v i t ie ie s .
Causes of Color Blindness Unlike other vision problems that we have been discussing above, color blindness or color vision deficiency is hereditary and is passed down in the f a m i l y . I t i s t h e X c h r o m o s o m e t h a t i s r e s p o n s i b le le f o r c a r r y i n g t h i s c o n d i t i o n and this explains why men are more likely to be color blind than women. Nonetheless, some people may also contract this condition from the effects of long-standing diseases that may include multiple sclerosis, liver diseases, diabetes or some major types of eye diseases. If this condition is inheritated, then it is unlikely that any change (better or w o r s e ) w i l l o c c u r ; t h e c o l o r b l i n d n e s s w i l l s i m pl y r e m a i n a s i t w a s a t b i r t h .
5. Blindness Blindness is defined as the inability to see anything. Being partially blind means that there is a limited ability to see things. A person who is c o m p l e t e l y b l i n d c a n n o t s e e a n y t h i n g a t a l l – j u s t l i k e b e i n g i n a p i t c h d a r k room.
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L e g a l b l i n d n e s s i s a t e r m t h a t i s u s e d t o r e f e r t o a h i g h l y c o m p r o m i s e d v i si si o n ability: A p e r s o n w h o h a s h e a l t h y e y e s c a n s e e a n o b j e c t f r o m a d i s t a n c e o f 2 0 0 f e e t ; however, a legally blind person will only be able to see that object if the p e r s o n i s s t a n d i n g a t a d i s t a n c e o f 2 0 f e e t f r o m i t .
Types of Blindness C o n s e n s u s i s t h a t t h e r e a r e t w o t y p e s o f b l i n d n e s s : p a r ti ti a l , o r c o m p l e t e . Partially blind people have limited vision and may suffer from blurred vision (see page 30 of this book for more details on Blurred Vision). T o t a l b l i n d n e s s , a s d e s c r i b e d a b ov e , r e s u l t s i n a c o m p l e t e b l a c k o u t f o r a person.
Causes of Blindness N u m e r o u s e y e d i s e a s e s a n d c o n d i t i o n s c a n l e a d t o b l i n d n e ss ss . W e w i l l b e d i s c u s s i n g t h e s e d i s e a s e s i n d e t a il il l a t e r i n t h e c h a p t e r . T h e y a r e a s f o l l o w s :
Macular Degeneration
Cataracts
Glaucoma
Optic Neuritis
Retinitis Pigmentosa
Tumors
Risk of Blindness The following people are at an increased risk of blindness:
Those who are suffering from a serious eye condition, including macular degeneration and glaucoma
Those who have diabetes
Those people who have had a stroke
Those people who have undergone an eye surgery
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T h o s e w h o w o r k i n h a z a r d o us us e n v i r o n m e n t s ( s u c h a s a r o u n d t o x i c chemicals)
Babies that are born prematurely
Blindness in Infants Eye diseases are not the only factors that are to be blamed for causing blindness. Some babies are born blind, while the eyesight of some infants begins to deteriorate soon after their birth. The visual system begins developing in the womb; however, the system usually does not develop until at least 2 years after birth. When the child is of around 6 to 8 weeks of age, the child may become able to fixate their gaze onto a moving object. By the time t h e c h i l d h a s r e a c h e d t h e a g e o f 4 m o n t h s , t h e e y e s s h o u l d ha v e b e c o m e properly aligned. It is recommended that the first eye e xamination be carried out w hen the child has reached the age of 6 months. Any of the following conditions can cause an infant to become blind:
A n y e y e i n f e c t i o n s , i n c l u d i ng ng , b u t n o t l i m i t e d t o t h e p i n k e y e
Any blocked tear ducts
Cataracts
Amblyopia (lazy eye)
Ptosis (drooped eyelid)
Strabismus (crossed eyes)
Congenital Glaucoma
Delayed development of the infant’s visual system
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Symptoms of Visual Impairment in Young Children Following are some of the symptoms that may indicate some kind of visual i m p a i r m e n t i n y o u n g c h i l d r e n. n. I f y o u f e e l y o u r c h i l d i s s h o w i n g a n y o f t h e f o l l o w i n g s y m p t o m s , h a v e t h e m c h e c k e d b y a p e d i a t r i c ia ia n .
Constantly rubbing eyes
S h o w i n g s s i g n s o f e x t r e m e s e n s i t i v i t y t o l i g h t ( p h o t o s e n si si t i v i t y )
Problems in focusing on objects
Chronic red eyes
A white pupil instead of a black one
Problems in keeping track of a moving object
Incorrect alignment or abnormal movement of the eyes
6. Eye Pain The technical name for eye pain is opthalmalgia. Eye pain is a common occurrence and usually is not an indication of a serious underlying condition. In most cases, the pain tends to go away without any need of treatment.
Types of Eye Pain Eye pain can be divided into two types depending on where a person is experiencing it. If a person experiences pain on the surface of the eye , then this is called
ocular pain. Pain that occurs within the eye is termed as orbital pain.
Ocular Pain Ocular pain generally feels as if something is being scratched on the surface o f t h e e y e . B u r n i n g o r i t c h i n g s e n s a t i o ns a r e a l s o c o m m o n . O c u l a r p a i n i s usually caused by external factors such as foreign objects, or as a result of an infection or even trauma.
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If any foreign object finds its way onto the surface of the eye, eye pain will be felt. Irritation, redness and running eyes along with the pain are common symptoms that indicate presence of a foreign object. There’s a tissue that lines the eye and the underside of your eyelid. If it is to
b e c o m e i n f e c t e d a n d i n f l a m e d a s a r e s u l t o f a n a l l e r g y – o c u l a r p a i n w i l l result. Inflammation of this tissue is known as conjunctivitis, more commonly known as the pinkeye.
Orbital Pain Orbital pain, on the other hand, is mostly caused by internal factors.
Glaucoma - Glaucoma sets in when the intraocular pressure (which is the blood pressure inside the e yes) begins to rise beyond normal levels. Glaucoma will be covered in more detail later on.
O p t i c N e u r i t i s – a n y i n f l a m m a t i o n o f t h e n e r v e t h a t c o n n e c t s t h e e y e to the brain will result in orbital pain.
S i n u s i t i s – S i n u s i t i s c a n a l s o c a u s e a b n o r m a l l e v e l s o f p r e s s u r e t o b u i l d up behind the eye, leading to eye pain.
M i g r a i n e s – M i g r a i n e s a r e y e t a n o t h e r f a c t o r t h a t c o n t r i b u t e s t o e y e pain.
I n j u r y – A n y i n j u r i e s t h a t c a u s e a f o r e i g n o b j e c t t o p e n e t r a t e i n t o t h e eye will cause great amounts of pain.
I r i t i s – T h i s i s r a r e , b u t i n f l a m m a t i o n o f t h e i r i s c a n r e s u l t i n p a i n inside the eyes.
Eye Conditions We have been discussing several types of visions some of which offer a clear warning of any underlying eye conditions. We will now proceed t o discuss the symptoms, causes and other useful information about these eye conditions. Please note that if you’re experiencing any symptoms of any of the following
eye conditions, it is imperative that you immediately see your doctor.
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A s m a n y o f t h e c o n d i ti ti o n s a r e d u e t o s o m e s o r t o f r e f r a c t i v e e r r o r s i n t h e eye, it is important to understand what refraction is and how it affects our vision.
Refraction: What is it? Simply put, refraction is nothing but the bending of light as i t passes f rom one medium to another. Vision is dependent on refraction, because as the light enters the eye, it is refracted by the cornea and the lens onto the retina. The light that is
focused onto the retina causes the retina to generate visual message which in turn are transmitted to the brain for processing.
Presbyopia Presbyopia is often referred to as an aging eye condition. It is quite common among aging people and in results in a loss of their ability to focus; thus making it difficult to see close-up objects. It is a problem that is associated with refraction, or the improper refraction - to be more precise, in the eyes.
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How Does Presbyopia Occur? A s p r e v i o u s l y m e n t i o n e d , p r e s by by o p i a o c c u r s a s p e o p l e a g e . T h e l e n s o f t h e eye hardens and this causes the light to be improperly refracted and thereby the incoming light is not correctly focused onto the retina. The muscles around the lens are also affected as a person ages, and this makes it difficult for a person to focus on close -by objects: the ineffective lens focuses the light behind the retina. A young person has a lens that is extremely soft and flexible a nd this allows the muscles to adjust the shape of the lens based on what the person is t r y i n g t o f o c u s u p o n – w h e t h e r c l o s e o r d i s t a n t o b j e c t s .
Who May Be Affected By Presbyopia? Whenever a person crosses the age of 35 years, they are exposed to the r isk of developing presbyopia. However, every other person experienc es some sort of loss in their ability to focus onto near objects, the extent to which they experience it, differs.
Symptoms of Presbyopia A p e r s o n w h o m a y b e s u f f e r i n g f r o m p r e s b y o p i a w i l l e x p e r i e n c e t h e f o l l o w i ng ng signs and symptoms:
Problems in reading small prints
Inability to view close-up objects, making them hold the object at a distance greater than an arm’s length in order to view it
Frequent Headaches
Eye Strain
Blurred vision at normal reading distances
H o w C a n P r e s b y o p i a B e D i a g n o s e d a n d C o r r e c t e d? d? A comprehensive eye examination can reveal presbyopia. If any o f the above symptoms are experienced, the person should pay a visit to an eye specialist. Eye exams should be increased in frequency as a person reaches 40 years of age.
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Eyeglasses can provide a temporary solution by directing the incoming light onto the correct part of the retina. However, certain eye exercises can help in strengthening the ey e s and can s i g n i f i c a n tl tl y c o n t r i b u t e t o a l e s s e r d e p e n d e n c y o n g l a s s e s o r c o n t a c t l e n s e s .
Myopia (Nearsightedness) M y o p i a i s a l s o c o m m o n l y k n o w n a s n e a r s i g h t e d n e s s . I t i s a c o n d i ti ti o n i n w h i c h objects that are close to a person appears clearly, but those that are at a distance, appear blurred.
How Does Myopia Develop? Unlike presbyopia, myopia is not an age-related condition. It can occur at any age and causes the eye to focus light in front of the retina. This is the result of the eye ball becoming too long. It is also known to be
caused b y an abnormality in the shape of either the cornea or the lens.
Who May Be Affected By Myopia? Age is not a factor for development of myopia; it can affect both adults and children. Quite often, nearsightedness is diagnosed in children bearing ages of between 8 and 12. The
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condition may get worse as they approach they become teenagers. Little changes are expected in the age band of 20 to 40; however, in particular cases, the condition may continue to get worse with age. Those people whose parents are shortsighted may also be at a greater c h a n c e o f d e v e l o p i ng ng m y o p i a .
Symptoms of Myopia Common symptoms associated with myopia include:
Eye Strain
Headaches
Squinting in an attempt to see properly
Difficulty in seeing far-off objects; children that have myopia often have trouble is seeing the blackboard clearly, especially if th ey are seated at the back of a classroom
T h e p r e s e n c e o f t h e s e s y m p t o m s m a y i n d i c a t e m y o p i a – s e e y o u r e y e c a r e professional immediately.
How Can Myopia Be Diagnosed and Corrected? An eye care professional can diagnose myopia during a detailed eye examination. Myopia can be temporarily corrected by wearing glasses or contact lenses. There are also natural ways of correcting myopia by consuming a healthy diet, by maintaining a healthy lifestyle and performing a series of exercises which will be covered later on in this book. These natural ways can have great effects on reducing, or sometimes eliminating the need and dependence on glasses and contact lenses.
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Hyperopia (Farsightedness) H y p e r o p i a i s a l s o c o m m o n l y k n o w n a s f a r s i g h t e d n e s s , b e c a u s e t h i s c o n d t i o n does not affect a person’s ability to see distance objects, a s compared to the
reduced ability of viewing closer objects. N e v e r t h e l e s s , f a r s i g h t e d ne ne s s v a r i e s i n i t s n a t u r e f r o m p e o p l e t o p e o p l e . A number of people may not even notice any problems with their vi sion at all, especially when they are young. For others, farsightedness may be considerable enough to make their vision blurred for both near and far objects.
How Does Hyperopia Develop? When the eyes begin to focus images onto the back of the r e t i n a , r a t h e r t h a n o n t o i t – farsightedness is said to have developed. As opposed to an elongated eyeball as in myopia, the eyeball tends to become c o m p r e s s e d o r s h o r t e n e d. d. It may also result due to an irregular shape of the cornea or the lens which would cause the light to be focused onto an incorrect portion of the eye.
Who May Be Affected By Hyperopia? Hyperopia can affect adults and
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children alike. It is estimated that around 5 to 10 percent of Americans are a f f e c t e d b y h y p e r o p i a – a p e r c e n t a g e m u c h l e s s t h a n t h a t o f p e o p l e h a v i n g myopia (30 percent). If the parents have hyperopia, then their children are more likely to develop it.
Symptoms of Hyperopia The symptoms of hyperopia are known to vary from person to pers on. Most people experience some or all of the following:
Eye Strain
Headaches
Squinting in order to try to see clearly
Blurred vision, especially when trying to bring closer objects into focus
How Can H yperopia Be Diagnosed and Corrected? An eye examination can reveal whether a person has hyperopia. Those people that visit an eye care professional with complaints of vision problems often c o m p l a i n a b o u t b l u r r y v i s i o n a n d d i s c o m f o r t. t. Eye glasses are, again, a solution to correct farsightedness. Contact lenses can also do the same job while a more invasive method of surgery is also an option. If you’re willing to reduce your dependency on glasses and contact lenses,
then you can try to improve your vision in more natural ways by leading a healthier lifestyle and by exercising your eyes.
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Astigmatism
A s t i g m a t i s m i s y e t a n o t he he r t y p e o f r e f r a c t i v e e r r o r i n t h e e y e . I t i s a condition where the eye is not able to focus light evenly onto the retina, thereby affecting vision.
H o w D o e s A s t i g m a t i sm sm D e v e l o p ?
FACT: Astigmatism alters
A normal eye consists of a cornea that has a
the natural curvature of
curvature similar to that of a basketball. This curvature focuses the incoming light evenly onto
the eye, causing an uneven distribution of the incoming light.
the retina. However, an eye with astigmatism has a cornea that is shaped more like a football; this causes the curvature to be uneven as some areas are steeper or more rounded. This cornea focuses light unevenly onto the corne a.
Who May Be Affected By Astigmatism? Astigmatism is not dependent on age, and can affect the vision of both adults and children. Astigmatism will affect each person differently; some
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people who have slight astigmatism may not even notice any kind of change in their vision.
Symptoms of Astigmatism The signs and symptoms of Astigmatism are similar to that of other eye disorders, with some additional indicators:
Eye Strain
Headaches
Squinting in an attempt to clear up
the vision
Blurry vision or distortions in the
vision for all distances
Figure 5: This is how a perso n with astigmatism might see.
Problems in driving at night
How Can Astigmatism Be Diagnosed and Corrected? A detailed eye examination can reveal whether or not a person is suffering from astigmatism. If any of the above symptoms are experienced then t he e y e s s h o u l d b e e x a m i n e d b y a p r o f e s s i o n a l e y e c a r e s p e c i a l i s t i m m e di di a t e l y . Eye glasses and contact lenses can correct the refractive error . A more permanent, yet invasive, method is refractive surgery to change the shape of t h e c o r n e a . T h i s t e n d s t o r e s t o r e t h e n a t u r a l f o c u si si n g p o w e r o f t h e e y e . Nevertheless, astigmatism can be reduced by leading a healthy lifestyle along with performing appropriate eye exercises.
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Glaucoma
Glaucoma is a vast term that covers a number of eye conditions; there’s one
thing that is same to all of these conditions and that is the fact that all of them damage the optic nerve. It is the optic nerve which carries the visual i n f o r m a t i o n t o t h e b r a i n f o r p r o c e s s i n g . I f t h i s n e r v e i s d a m a g e d , v i s i o n wi l l be seriously affected. Glaucoma is serious; it is the second most common condition that leads to b l i n d n e s s i n t h e U S – t h e f i r s t b e i n g c a t a r a c t . As a result of glaucoma, large gaps begin to appear in a person’s field of
vision. The field of vision is the range a person is able to vi ew (see Chapter 1 How the Eye Works).
What is G laucoma? Glaucoma is a set of conditions that are associated with increasing pressure inside the eye. This pressure is called the intraocular pressur e.
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A fluid called aqueous humor is located at the front part of the eye, and it is made just behind the iris. It circulates around the channels at the fron t of the eye in an area which we call the anterior chamber angle. If for any reason, this flow is slowed down or blocked, this fluid will te nd to cause the pressure to build up (intraocular). The pre ssure build-up tends to damage the optic nerve. Four major types of glaucoma are present, each having different characteristics:
1. Open-Angle Glaucoma (chronic) 2 . A n g l e - C l o su su r e G l a u c o m a ( a c u t e ) 3. Congenital Glaucoma 4. Secondary Glaucoma Open-Angle Glaucoma (Chronic) This is the most common type of glaucoma and the cause of its d evelopment is not clearly known as of yet. The increase in pressure is slow and steady; the pressure builds up until it pushes against the optic nerve. It is hereditary and runs in families. This type of glaucoma does not show any symptoms until after considerable damage has occurred to the eye.
Angle-Closure Glaucoma (acute) The angle-closure glaucoma is known to occur when the exit points of the fluid are blocked abruptly. This results in a rapid, severe and painful increase in the intraocular
Figure 6: An eye suffering from acute glaucoma.
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pressure. This is a severe condition, and an emergency situation arises w hen it oc curs. Compared to open-angle glaucoma which is slow yet painless; angle-closure glaucoma is quite sudden and painful to endure. Those people who already have this type of glaucoma in one eye are at a greater risk of an a ttack on the other one.
Congenital Glaucoma I n f a n t s a r e p r o n e t o h a v e c o n g e n i t a l g l a uc o m a i f i t r u n s i n t h e f a m i l y . I t i s usually present at the time of birth and is caused by an abnormal d e v e l o p m e n t i n t h e v i s u a l s y s t e m – m o r e p r e c i s e l y , t h e e y e .
Secondary Glaucoma Secondary glaucoma can result by other eye conditions, by use of certain medications and other medical conditions. This type of glaucoma can also have been inherited, which then can be further divided into two types: -
Pseudoexfoliation (PEX) syndrome is discernible as flakes that are s i m i l a r t o d a n d r u f f . T h e s e c a n a c c u m u la t e o n t h e l e n s o f t h e e y e a n d c l o g t h e d r a i n a g e o f t h e f l u i d ( a q u e o u s h u m o r ) ; t h e r e b y l e a di n g t o a n i n c r e a s e i n i n t r a o c u l a r p r e s s ur ur e .
P E X h as a s a s t u r d y g e ne ne t i c c o m p o n e n t
but other triggers such as sunlight, a slow virus or the response of the autoimmune system may be needed. -
Pigmentary Glaucoma begins with a condition which we call the p i g m e n t d i s p e r s i o n s y n d r o m e . T h i s i s a n i n h e r i t e d c o n d i t i o n w h i c h causes the granules of pigments to ‘flake-off’ into the fluid (a queous
humor). These flakes tend to clog the drainage and in turn increase the ocular pressure.
Risk of Glaucoma Glaucoma is the second highest cause of blindness in the United States after cataracts. Over 4 million Americans have open-angle glaucoma and more than
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half of them are not aware because no clear symptoms of this type of glaucoma are noticeable until it is too late and the damage has been done. Some of the factors that bring on the risk of developing glaucoma are as follows:
I n c r e a s e i n I n t r a o c u l a r P r e s s u r e – E l e v a t e d l e v e l s o f i n t r a o c u l a r pressure can damage the optic nerves and cause development of glaucoma.
A g e – A g e i s a m a j o r f a c t o r w h e n i t c o m e s t o g l a u c o m a . T h e r i s k o f d e v e l o p i n g g l a u c o m a i n c r ea ea s e s c o n s i d e r a b l y a s t h e a g e o f a p e r s o n increases. Each and every person over the age of 60 years is at a g r e a t e r r i s k o f d e v e l o p i n g g l a u c om a . S o m e e t h n i c g r o u p s , s u c h a s t h o s e of an African descent, are more prone to develop glaucoma even at a younger age.
R a c e a n d E t h n i c i t y – R a c e a n d e t h n i c i t y i s a m a j o r r i s k f a c t o r w h e n i t comes to developing glaucoma. People of African origin are a p p r o x i m a t e l y f i v e t i m e s m o r e l i k e l y t o d e v e l o p i t t h a n C a u c a s i a n s. s. They are also four times more likely to become blind as a r esult of it. People of Japanese ancestry are at a g reater risk of developing closedangle glaucoma as compared to other races.
F a m i l y H i s t o r y o f G l a u c o m a – G l a u c o m a i s i n h e r i t a b l e a n d r u n s d o w n the family line. Open-angle glaucoma is more likely to be passed down to newer generations as compared to the other types of glaucoma.
M e d i c a l C o n d i t io i o n s – S e v e r a l m e d i c a l c o n d i t i o n s s u c h a s d i a b e t e s a n d h y p e r t h y r o i d is is m a r e a s s o c i a t e d w i t h a n i n c r e a s e d r i s k o f g l a u c o m a . Other conditions such as high blood pressure as well as migraine may also contribute to the i ncreased risk. Even certain eye conditions such as myopia may heighten the chances of the development of glaucoma.
Symptoms of Glaucoma
S y m p t o m s o f O p e n - A n g l e G l a u c o m a : T h i s i s a c h r o n i c c o n d i t i o n t h a t develops slowly over the years and no pain or any kind of visual changes are experienced in its early developing stages. However , as it
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progresses, the optic nerve is damaged over time and then the f o l l o w i n g s y m p t om om s s t a r t t o a p p e a r i n t h e a f f e c t e y e o r e y e s :
sh a n d p e o p l e s t a r t t o d e v e l o p 1 . P e r i p h e r a l V i s i o n s t a r t s t o d i m i n i sh tunnel vision in which they are only able to see straight ahead.
2. The next symptom that follows is the decrease in the tunnel vision, steadily decreasing the field of view of the person. I f a t t h i s p o i n t t h e c o n d i t i o n i s l e f t u n t r e a t e d , b l i n d ne s s w i l l f o l l o w .
S y m p t o m s o f A n g l e - C l o su s u r e G l a u c o ma ma : T h i s i s a m o r e s e v e r e t y p e o f g l a u c o m a a s t h e s y m p t o m s a r e q u i t e o b v i o us us a s s o o n a s t h e p r e s s u r e starts to rise rapidly. Intense pain is felt in the area surround the eyebrows along with development of blurry vision, usually in a s ingle eye. A person may also feel as of their eye is about to burst. Redness follows together with rainbow-like halos around sources of ligh t. Nausea and vomiting are also known to occur. All of these symptoms appear randomly and not at all as a full-fledged attack.
Symptoms of Congenital Glaucoma: A baby is usually born with congenital glaucoma if it runs in the family. However, no symptoms may appear until the baby is of a few months of age. If an infant’s eyes are observed as becoming cloudy, watery, enlarging or if the infant
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s h u t s t h e i r e y e s w h e n t h e y s e e l i g h t – a n o p h t h a l m o l og og i s t m u s t examine the infant’s eyes.
Treating Glaucoma G l a u c o m a i s u s u a l l y t r e a t e d w i t h m e d i c a t i o n , l a s er t h e r a p y o r e v e n s u r g e r y . The aim of the treatment is to bring down the intraocular pressure in order to reduce the risk of the person going blind. It is estimated that between 4 to 20 people out of a total of 100 who have high intraocular pressure may lose their vision in just under 5 years time. However, this time is dependent on the following factors:
The amount of intraocular pressure in the eye
The thickness of the cornea
The person’s age
This is why it is important to l ower the intraocular pressure in order to r e d u c e t h e r i s k o f a p e r s o n l o s i n g t h e i r v i s i o n. n. G l a u c o m a i s a c o n d i t i o n t h a t cannot be cured because the damage to the optic nerve is irreversible. However, the intraocular pressure can be lowered to prevent further damage by means of eye drops. If t he eye drops fail to bring down the pressure, then surgery becomes the last resort in lowering the pressure permanently down to appropriate levels. Due to the seriousness of this eye condition, along with the discrete approach (in the case of open-angle glaucoma), ophthalmologists recommend regular eye checkups so that any developing condition can be spotted before it gets too late.
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Cataract A cataract is the clouding of your eye’s lens which leads to a decrease in visual acuity. The lens in the eye is responsible for focusing the incoming light onto the retina, where the visual images are captures by l i g h t - s e n s i t iv iv e r e t i n a a n d transmitted through the optic nerve to the brain for processing. The clouding diminishes the amount of light that is able to enter the eye. As the cataract progresses and becomes mature, glare, contrast and color sensitivity are experienced besides the decrease in vision.
C a u s e s o f C a t a r a c t D e v e l o p m en en t Protein and water are the main components of which the eye is made of. The protein is set in a way that it allows the passage of light while keeping the lens clear. The cataract begins to develop when some of this pr otein starts to cluster together, thus clouding the lens. Cataract is not contagious and it does not spread from one eye to the other; however, for most people, it develops in both eyes at the same time. There are a number of causes of cataracts, and they are as follows:
A g i n g – T h e m o s t c o m m o n c a u s e o f c a t a r a c t s
Diabetes
Smoking
Eye Infection
Injuries to the eye
Exposure to high levels of radiation
Excess exposure to sunlight (UV radiation)
A Birth defect
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Risk of Cataract Risk factors are those particular aspects that increase the chance of developing or acquiring a disease. C hances of developing cataracts are increased by:
Increasing Age
Excessive Exposure to Ultra Violet-B radiation
Family members who have cataracts
Diabetes
Trauma
Smoking
S y m p t o m s o f C a t a r a ct ct s
I n t h e e a r l y s t a g e s o f c a t a r a c t d e v e l o pm pm e n t , p e o p l e m a y n o t n o t i c e a n y changes in their vision at all. Cataracts are known to mature at slow rates and this causes a slow-yet-steady decrease in the vision. Some people sometimes experience a sudden improvement in their close-up vision; however, this is short lived. As the cataract continues to mature and cloud the lens, the vision decreases. A lot of people do not realize that they h a v e c a t a r a c t u n t i l i t i s d i s c o v e r e d d u r i n g a n e y e e x a m i n a t i o n. n. People with cataracts usually experience the following symptom s as the cataract matures:
Blurred vision or cloudiness
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Increased sensitivity to light; the headlights of oncoming cars may seem too bright at night.
Glare from bright sources of light
A halo is seen around lights
The colors appear to be faded and not as bright as they were
Rapid changes in glasses or contact lenses prescription
Nevertheless, a lot of eye conditions have similar symptoms. If any of the above symptoms are experienced, it is better to undergo a detailed eye examination as the eye specialist would be better able to determine the reason behind your vision problems.
Diagnosing Cataracts Looking at the symptoms above, you may feel as if you have a cataract. H o w e v e r , t h e o n l y w a y t o r e a c h t h a t c o n c l u s i on on i s t o u n d e r g o a d e t a i l e d e y e e x a m i n a t i o n . A n e y e s p e c i a l i s t w i ll p e r f o r m a n u m b e r o f t e s t s t o f i g u r e o u t the overall health of your eye. You can expect the following to be a part of a detailed eye examination: V i s u a l A c u i t y T e s t – T h i s i s a n e y e c h a r t t e s t t h a t h e l p s i n d e t e r m i n i n g h o w w e l l a p e r s o n c a n s e e f r o m v a r y i n g d i s t a n c e s. s. Pupil Dilation- The pupil in the eye is widened using eye drops in order to be able to see more of the lens and the retina during the exam T o n o m e t r y – T h i s i s a s t a n d a r d t e s t t h a t i s u s e d t o m e a s u r e t h e i n t r a o c u l a r pressure of the eye. I ncreased eye pressure may lead to development of Glaucoma (see page 44 of this book).
T r e a t i n g C a t a r a ct ct s When the cataract is in its early stages, there are chances that the vision can be improved by using eye glasses. If they fail to work, or if the loss of vision has become severe enough to interfere in your day to day activities such as reading, watching television and driving, then the other option that remains is surgery.
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Cataract surgery does not require to be pe rformed on an urgent basis; this means that you can wait until you are ready for the procedure. However, the cataract will continue to mature and the cloudiness will become more and more prominent. The surgery requires removal of the clouded lens and replacemen t by an intraocular lens in its position. The intraocular lens then beco mes a permanent part of your eye and requires no care at all. After the surgery is successful, some people may need reading glasses to read clearly, while some may need glasses to see dist ant objects clearly. H o w e v e r , i f t h e c l o u d y l e n s w a s r e p l a c e d b y a m u l t i f o c al al i n t r a o c u l a r l e n s , glasses will not be required for either purpose.
Prevention C a t a r a c t s c a n n o t b e c o m p l e t e l y a v o i de d ; n o n e t h e l e s s , t h e c h a n c e s o f developing one can be r educed significantly by leading a healthy lifestyle that includes plenty of exercise as a part of y our daily routine. The following can also help in reducing the risk of developing a cataract:
Quit Smoking
Consume antioxidant vitamin supplements
Protect yourself from excessive exposure to the sun by wearing sunglasses with UV protection as well as a hat
Regular eye examinations should also be carried out, especially when a person crosses the age of 60 years.
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Age-Related Macular Degeneration
Age-Related Macular Degeneration is a c o m m o n t y p e o f e y e c o n d i ti ti o n t h a t c a u s e s the deterioration of the central part of the retina which we call macula. The retina is a thin layer of tissue at the back of the eye and consists of light-sensitive cells that capture light and transmit the visual signals to the brain through the optic nerve. We use macula to view the fine details of an image; everyday activities such as reading, watching television, recognizing people’s faces and any other
visual activities that require detailed analysis are the work of macula. The major factor that is responsible for degeneration of macula is age.
T y p e s o f A g e - R e l a t ed ed M a c u l a r D e g e n e r a t i o n There are two types of age-related macular degeneration (AMD) and any person can develop both types of AMD. The rate with which the disease develops also varies from person to person; it can either develop at a slow or fast pace. The types are:
Dry age-related macular degeneration
Wet age-related macular degeneration
Dry age-related macular degeneration This is the most common type of macular degeneration. Macula is the central p a r t o f t h e r e t i n a a n d i s t h u s c o m p o se s e d o f l i g h t - s e n s i t i ve ve c e l l s . I n t h i s particular type of AMD, the cells break down at a slow rate.
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When the cells begin to break down, yellow d eposits which are called drusen are deposited under the retina. Drusen deposits are commonly found in the eyes of older people. However, any significant increase, whether in quantity or size, can indicate that the macular is degenerating. D r y A M D c a n c o n t i n u e t o d e v e l o p a n d c a u s e s i g n i f i ca ca n t v i s i o n l o s s w i t h o u t transforming into wet macular degeneration. On the other hand, it is also possible that dry macular generation may change into the wet type in its early stages.
W e t a g e - r e l a t e d m a c u l a r d e g e n e r a t i on It is not unusual to have wet macular degeneration follow the dry type. In the wet type of this disease, Bruch’s
membrane (that is a barrier that supports the retina) begins to break down. This breakdown normally happens in close proximity to drusen deposits. A growth of blood vessels takes place (neovascularization) as a result. These new blood vessels are
Figure 7: Neovascularization
apparently extremely fragile and are k n o w n t o l e a k b l o o d – l e a d i n g t o a g r e a t e r r i s k o f m a c u l a r s c a r r i n g a n d severely damaging it.
Neovascularization disturbs the natural systems of the
eye and can cause the vision to become vague or even completely lost within a few days or week’s time.
Only about 10 percent of AMD are of the wet-type; however, it is so serious that over 90 percent of the time, patients with this condition go legally blind.
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S y m p t o m s o f A g e - R e l a t e d M a c u l ar a r D e g e n e r a t io io n
The following symptoms may i ndicate macular degeneration:
Difficulty in reading or in performing everyday a ctivities such as driving and watching television
Having a distorted vision which causes straight lines to appear bent
Problems in recognizing faces of people
Dark patches appear at the center of your field of vision
Age-related macular degeneration can develop in one eye only. However, as the disease develops, both the eyes may begin to be affected by it. If you have AMD in one eye only, it is v ery likely that your other eye will also be affected.
Treating Macular Degeneration Presently, no cure is available for age-related macular degener ation. It is a progressive disease and the treatments that are available can only help to provide the best vision possible for as long as feasible. There are a number of medications available for people with wet macular d e g e n e r a t i o n t o h e l p c o n t r o l n e o v a s c ul ul a r i z a t i o n ( a b n o r m a l b l o o d v e s s e l growth and the leaking of blood or fluid) in order to minimize the damage to the retina.
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Risk Factors Following are the risk factors that increase chances of developing macular degeneration:
People aged 50 and above are at a greater risk
Smoking is known to increase the risk
If macular degeneration runs in the family, newer generations a re more likely to develop it
Charles Bonnet Syndrome In some cases, macular degeneration is known to cause phantom i mages to appear. Whatever these images show, the object is actually not present. These images can range from being as simple as random lines to as complex a s p e o p l e a n d b u i l d in in g s . The frequency of these images can be several times in a month, in a week or perhaps even daily. This phenomenon tends to go away once the brain adjusts to the vision problems.
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Amblyopia A m b l y o p i a i s c o m m o n l y r e f e r r e d t o a s a l a z y e y e . I t i s a c h i l d h o o d d i s o r d e r as a result of incomplete development of the vision system in the early years o f a n i n d i v i d u a l ’s ’s c h i l d h o o d .
Infants are not born with a 20/20 vision. They develop their vision system from birth till an age of around 6 years. T his development takes place when identical images are formed on retinas of both the eyes. If they do not, vision does not properly develop and the affected eye thereby becomes amblyopic. It is estimated that around 4 percent of children experience this condition. If the vision is to be prevented from deteriorating, this condition must be d i a g n o s e d a n d t r e a t e d d u r i n g t h e e a r l y c h i l d h o o d y e a r s. I f t h e t r e a t m e n t i s p u r s u e d a f t e r t h e a g e o f 6 – i t i s v e r y l i k e l y t h a t r e s t o r i n g v i s i o n b e c o m e s a n impossible task.
Causes of Amblyopia There are three factors that can cause a child’s eye to become amblyopic.
1 . S t r a b i s m u s – M i s a l i g n e d E y e s Misalignment of the eyes is a mong the most common reasons for causing amblyopia. In a situation where the eyes are not aligned and aimed in the similar direction, the brain ignores the image from the eye that is
Figure 8: A child with strabismus
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a s s u m e d t o b e m i s a l i g n e d i n o r d e r t o p r e v e n t d o u b l e v i s i o n. n. T h i s r e s u l t s i n the child using the ‘correct’ eye only. If this continues for even a few weeks, the eye will fail to establish a correct link to the visual cortex of the brain.
2 . A n i s o m e t r o p i a – U n e v e n R e f r a c t i v e E r r o r The refractive error has to be the same in both eyes in order for the eyes to be able to focus simultaneously. This causes the eye with the g reater refractive error to become amblyopic. This situation again caus es one eye to become more dominant than the other; robbing the other eye’s chance to
d e v e l o p n o r m a l v i s i o n . C o m p a r e d t o m i s al al i g n e d e y e s , a n i s m e t r o p i a i s f a r more difficult to detect as both the eyes look similar. Only thorough examinations that focus on visual acuity and ocula r preference tests can detect this cause.
3 . D e p r i v a t i o n – O b s t r u c t i o n i n t h e V i s u a l S y s t e m If any sort of obstruction is present on eye tissues, then this can result in a m b l y o p i a . A n y t y p e o f e y e c o n d i t i o n t h a t a c t s a s a h i n d r a n c e i n f o r m i ng ng o f a clear image onto the retina will consequently become the cau se of development of amblyopia (cataract, for example).
Recognizing Amblyopia I t i s n o t a t a l l e a s y t o i d e n t i f y a m b l y o p i a a s i t i s d i f f i c ul ul t ( a n d i m p o s s i b l e , i n some cases) for a child to identify a reduction is vision. A child may not even be aware the problem as adults would be, because they have no e xperience that they can compare it to. T h e o n l y p o s s i b i l i t y t h e r e i s o f a n a d u l t i d e n t i f y in g t h i s p r o b l e m i n a c h i l d b y visual examination is an external abnormality such as misalignment of the eyes. T h e o t h e r c a u s e s m a y o n l y b e d e t e c t e d t h r o u g h a t h o r o u g h e y e e x a m i n a ti ti o n by an eye specialist.
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Risk Factors Here are some of the factors that will amplify the chances of a child developing this disease:
Family History of cataracts, glaucoma or ambyopia itself
N u m e r o u s o t h e r g e n e t i c c o n d i t i o ns o f t h e e y e
Pediatric Cataracts
Ptosis (droopy eyelids)
Tumor in the eyelid which blocks the pupil
Tests for Diagnosing Amblyopia T h e f o l l o w i n g t e s t s m a y b e p e r f o r m e d o n a c h i l d t o d e t e c t a n y d e v e l o p me me n t o f a m b l y o pi pi a :
Cycloplegic Refraction
Slit Lamp Exam
Visual Acuity Measurement
Fundus Exam
Detailed Eye Exam
Treating Amblyopia As we previously discussed that a child begins to use only one eye because the brain shuts off the images from the other ‘faulty’ eye.
To ensure proper development of both the eyes, a child must be forced to use both eyes (especially the weak one). This can be achieved b y correcting any factors that may be leading towards amblyopia. In some cases, s p e c i a l i s t s r e c o m m e n d p a t c h i n g t h e s t r o n g e r e y e s o t h a t t h e w e a k e y e i s used by the child. In some cases, glasses are used to treat amblyopia. Children usually do not understand the reasons behind all the treatment methods, and as a parent, it is your responsibility to make sure their treatment is not affected as a result o f t h e i r d i s c o m f o r t t o w a r d s p a t c h i n g , g l a s se s o r e y e d r o p s .
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Ptosis (Drooping Eyelids)
Figure 9: Ptosis can affect one, or both eyes. It is the upper eye lid that droops, as can be seen in this picture.
D r o o p i n g o f a n e y e l i d i s c a l l e d p t o s i s . T h i s i s a c o n d i t i o n i n w h i c h t h e u p p e r part of the eyelids falls to a position that is lower than the normal. Depending on the severity of this condition, the eyelid can dro p down to an e x t e n t t h a t i t c o v e r s p a r t o r w h o l e o f t h e p u p i l – t h e r e b y a f f e c t i n g v i s i o n . Ptosis can affect one or both of the eyes and is a condition that may be p r e s e n t a t b i r t h o r m a y e v e n d e v e l o p i n t h e l a t e r y ea r s o f o n e ’ s l i f e . In several of the cases, ptosis is an isolated issue that does not affect the overall health of a person without even deteriorating the vision at all. On the other hand, for some, it can be an indication of other severe conditions that may be affecting the muscles, brain, nerves or socket of the eye.
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W h e n a p t o s i s d e v e l o p s w i t h i n a p e r i o d o f s e v e r a l d a y s o r h o u r s – i t b e c o m e s an alarming indication of a prevailing medical condition.
Causes of Ptosis H e r e a r e s o m e p o s s i b le le c a u s e s t h a t m a y l e a d t o d e v e l o p m e n t o f p t o s i s :
C o n g e n t i c a l P t o s i s ( A t B i r t h ) – T h i s i s a c o n d i t i o n t h a t a n i n f a n t i s b o r n w i t h . It could be due to a problem in the development of the involved eye muscles (levator muscle). Only one eye is affected in 70 percent of the c ases. If the eye lid is drooping down enough to block the pupil, then a corr ective surgery m u s t b e p e r f o r m e d i n o r d e r t o p r e v e n t a n y v i s i o n p r o bl bl e m s .
A p o n e u r o t i c P t o s i s ( A g e - R e l a t e d ) – A g i n g i s a c o m m o n c a u s e o f t h e weakening of the muscles around the eyelids. This condition is caused by the accumulated effects of gravity and increasing age that weaken the tissues involved in assisting levator muscle in performing its job. If this is the cause of the development of ptosis, then both the eyes are likely to be affected. ia g r a v i s i s a r a r e c o n d i t i o n t h a t a l t e r s t h e M y a s t h e n i a G r a v i s – M y a s t h e n ia way muscles react to nerve inputs. This condition is known to progressively weaken muscles. These muscles are not limited to the eye lid ar ea, but also those that of arms, legs, fa ce and other body parts. H o w e v e r , t h e w e a k e n i n g o f m u s c l e s s u r r o u n di n g t h e e y e l i d l e a d t o p t o s i s and it is extremely likely that both eyes will be affected.
O c u l o p h a r yn y n g e a l M u s c u l a r D y s t r o p h y ( O M D ) – O M D i s d i s e a s e t h a t i s usually passed down the family tree into new generations. This disease a f f e c t s t h e m u s c l e s a n d c a n s i g n i f i c a n tl tl y a f f e c t e y e m o t i o n a s w e l l a s i n d u c e d i f f i c u l t y i n s w a l l o w i ng . T h i s c o n d i t i o n c a n a l s o l e a d t o p t o s i s in both eye lids.
N e r v e P r o b l e m – T h e b r a i n c o n t r o l s t h e m u s c l e s b y s e n d i n g s i g n a l s through the nerves. If a ny sort of condition develops that damages the brain or the i nvolved nerves, then it is extremely likely that ptosis will follow. Nerves can also be damaged as a re sult of diabetes.
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Horner’s Syndrome is yet another factor that can lead to ptosis. This
syndrome causes the pupil to be come unusually smaller while half the face loses its ability to excrete sweat.
O t h e r E y e C o n d i t i o n s – O t h e r p r o b l e m s r e l a t e d t o t h e e y e c a n a l s o cause ptosis. An infection, tumor or trauma is among leading factors that are responsible for the onset of ptosis.
Symptoms of Ptosis O n e o f t h e m o s t o b v i o us us s y m p t o m s o f p t o s i s i s t h e f a c t t h a t t h e e y e l i d seems to be drooped at a position that is lower than the normal point. This is easier to spot if ptosis is only affecting a single eye. If ptosis advances to severe stages, then vision will be obscur ed as a result of the eye lid covering the pupil.
Treating Ptosis Mild symptoms of ptosis where vision i s not being affected do not usually require any treatment. Even when the treatment is required, it is carried out i n o r d e r t o r e s o l v e t h e u n d e r l yi yi n g c a u s e . In some cases, eye exercises are sufficient as they help in strengthening the w e a k m u s c l e s b y h e l p i n g t h e m t o r e t u r n t o t h e i r o r i g i n a l w o r ki n g s t a t e . I n other cases, use of eye glasses may be recommended by an eye specialist; t h e s e e y e g l a s s e s a r e n o t h i n g l i k e t h e o r d i n a r y – t h e y h a v e a c r u t c h a t t a c h e d to them whose function is to hold the eye lid up and prevent it from drooping down. When ptosis is found to be of a severe kind, the only option for correcting it may be surgery. The surgical process that corrects ptosis is called
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blepharoplasty.
This surgical procedure involves the tightening of lev ator muscles, which in turn lift the drooping eyelids that may be interfering with normal vision. In most of the cases, after the surgical process is complete, no loss of eyelid movement is reported. The surgery does not guarantee that the eyelids will be perfectly symmetrical; however, they will definitely be at a higher position than before.
Complications Untreated ptosis in children can lead to a condition called the amblyopia (see page 54 of this book). If the amblyopia is also left untreated, then the child’s vision will surely deteriorate.
Complications after blepharoplasty include:
Excessive bleeding
Forming of blood clots
Infection
Scarring
Asymmetrical muscles (facial)
Nerve damage (facial)
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Conjunctivitis
C o n j u n c t i v i t i s i s a n e y e c o n d i t i o n t h a t i s c o m m o n l y r e f e r r e d t o a s t h e p i n k eye. It is the inflammation of the outer layer of the eye, and causes the eye
to appear red or pink. Conjunctivitis is known to occur in both adults and children; however, children are more s usceptible to the infection that causes this condition to occur. It is a contagious condition that can spread extremely quickly from person to person. Children generally have a weaker immune system as compared to adults, and it is not uncommon to see pink eye spreading among the students at a school or children at day care centers. The eye has a clear membrane that lines the white part of an eye as well as lining the inner part of the eyelid know as conjunctiva. When either of these becomes inflamed, conjunctivitis is said to have occurred. This inflammation causes the blood vessels in the conjunctiva to enlarge, and this is precisely what makes the eyes appear red.
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T y p e s o f C o n j u n c t i vi vi t i s T h e r e a r e m a i n l y t h r e e t y p e s o f c o n j u n c t i v i t i s . T h e p i n k e y e c o n d i ti ti o n c a n b e c a u s e d b y a l l e r g i e s , b a c t e r i a , v i r u s e s o r i n t h e c a s e o f n e w b o r n b a b i e s – a block tear duct can be responsible. Here are the three types of pink eye: 1. Viral Conjunctivitis 2. Bacterial Conjunctivitis 3. Allergic Conjunctivitis
V i r a l C o n j u n c t i v it it i s V i r u s e s a r e a m o n g t h e m o s t c o m m o n c a u s e s o f c o n j u n c t i v i ti ti s . A d e n o v i r u s i s a virus that is known to cause the common cold, is also responsible for causing t h i s i n f l a m m a t i o n. S o m e o f t h e o t h e r v i r u s e s t h a t a r e t o b e b l a m e d f o r t h i s include:
Varicella-Zoster Virus
Picorna Virus
Pox Virus
Herpes Simplex Virus
Human Immunodeficiency Virus (HIV)
V i r a l c o n j u n c t i v i t i s t y p i c a l ly ly r e s u l t s i n a w a t e r y d i s c h a r g e f r o m t h e e y e s . Both the eyes contract it, even i f the infection only started with one, due to the contagious nature of this virus.
B a c t e r i a l C o n j u n c t iv iv i t i s The bacterial conjunctivitis is far more common in children as compared to adults. The bacteria that are known to cause this type of pink eye infection are:
Staphylococci
Streptococci
Gobococci
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Chlamydia
C o n t r a r y t o t h e w a t e r y d i s c h a r g e t h a t i s c a u s e d b y v i r a l c o n j u n c t i v i ti s , b a c t e r i a l c o n j u n c t i v i ti s c a u s e s a t h i c k d i s c h a r g e t o e m e r g e f r o m t h e e y e s c a n be of a yellow, white or green color. This discharge can make a person feel as if their eyelids are being ‘glued’ together, this feeling is more prominent when they wake up in the morning. Only one eye is more likely to be affected by the bacteria, however, this doesn’t mean that it cannot spread to the other eye.
A l l e r g e n i c C o n j u n c t iv iv i t i s Allergenic conjunctivitis is known to causes redness, itching a nd tearing in both the eyes. Discharge may also emanate from the nose and cause itching within. This is not a contagious type of conjunctivitis as it occurs when certain irritants are present in the environment (such as dusk and smoke).
S y m p t o m s o f C o n j u n c t i vi vi t i s The symptoms of each type of conjunctivitis differ slightly.
S y m p t o m s o f V i r a l C o n j u n c t iv iv i t i s
Redness in the eye, especially on the white area
An Itching or burning sensation on the eye lids
Swollen areas at the front of ears
Lots of tearing
Clear, watery discharge from the eyes
T h e s e s y m p t o m s t y p i c a ll ll y l a s t f o r 5 d a y s t o a w e e k . H o w e v e r , t h e i r d u r a t i o n may extend up to three weeks.
Symptoms of Bacterial Conjunctivitis
Redness in the eye, especially on the w hite area
Yellow discharge from the eyes that causes the eye lids to stick together; especially in the mornings
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Pain in the eyes
Swollen upper eye lids
T r e a t i n g C o n j u n c t i vi vi t i s Due to the fact that there are three different types of conjunctivitis, the treatment also varies. Viral conjunctivitis is typically caused the same virus that cau ses the common cold. Therefore, similar to the cold, virus conjunctivitis must also run its course which lasts from anywhere between 4 to 7 days. This is a highly contagious type of conjunctivitis and thus physical cont act should be avoided with the infected person. C o n j u n c t i v i t i s c a u s e d b y b a c t e r i a i s t r e a t e d w i t h a n t i b i o t i c s. s. T h e s e c o m e i n numerous forms, including eye drops, pills or ointments. Ointments or eye drops should be applied to the inner part of t he eye lid at least 3 to 4 times a day for duration of 4 to 7 days. Pills, on the other hand, should be consumed for a few days. The condition usually begins to improve within a week’s time.
Allergenic conjunctivitis tends to improve once the allergens have been removed. If any irritants have gotten into the eye, then the eye must be thoroughly washed with lots of clean water.
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Keratoconus
The literal meaning of Keratoconus is ‘a cone-shaped cornea’. The cornea
is the clear part which is located at the front of the eye. The cornea in its natural state can be described as being ‘dome-shaped’.
However, keratoconus occurs when the layers near the center of the cornea become thin, thereby causing the cornea to become pointy. There are some ways through which keratoconus can be corrected; however, those people who have received successful treatment continue to have reduced vision for the rest of their lives.
Causes of Keratoconus The eye consists of tiny fibers that are called collagen. The collagen are responsible for keeping the cornea in i ts right position and for preventing it from bulging out. The problem starts wi th the collagen becoming weak. This weakening leads to their inability to hold the cornea in i ts place; this causes the cornea to progressively develop a cone-shape. Keratoconus is hereditary; it runs in f amilies and people whose parents have i t a r e a t a g r e a t e r r i s k o f d e v e l o p i n g t h i s c o n d i t i o n. T h e c h a n c e s o f t h e development of this condition increases in people who have othe r types of medical issues. I t h a s b e e n o b s e r v e d t h a t k e r a t o c o nu nu s b e g i n s t o s e t i n d u r i n g t e e n y e a r s o f an individual’s life. However, it can also start e ven in a person’s childhood
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years. The chances of its occurrence start to diminish once the age of 30 years is crossed. The rate at which the cornea begins to change is variable; it can either take years, or i t may happen suddenly. Similarly, the changes can either stop all of a sudden, or cont inue to get worse. The highly variable nature of this condition makes it not so predictable. If one eye is affected, then it is likely that the other eye will also develop keratoconus, eventually.
Symptoms and Diagnosis of Keratoconus T h e s y m p t o m s o f k e r a t o c o n u s u s u a l l y s t a r t w i t h b l u r r i n g o f a p e r s o n ’ s v i s i o n. n. The changes in the eye glasses prescription also increase in fr equency up till a p o i n t w h e r e t h e i n d i v i d u a l ’ s v i si o n s i m p l y c a n n o t b e c o r r e c t e d w i t h e y e
g l a s s e s o r c o n t a c t l e n s e s . S o m e o f t h e o t h e r s y m p t o m s i n c l u d e t h e f o l l o w i ng :
I n c r e a s e d s e n s i t i v i t y t o l i g h t ( p h o t o s e n si si t i v i t y )
Difficulty in driving at night
Appearance of halos around light sources
Eye strain
Irritation of the eye (leading to excessive rubbing)
Headaches and pain in the eyes (to learn more about the types of eye p a i n , g o t o p a g e 3 5 o f t h i s b o o k )
As it can be seen, the above symptoms are not unique to keratoconus. All of t h e a b o v e s y m p t o m s a r e u s u a l ly ly a s s o c i a t e d w i t h s e v e r a l o t h e r e y e conditions. Therefore, it is not possible to diagnose ker atoconus by simply observing the symptoms. A thorough examination by an eye specialist is essential who has the ability to utilize both direct measurement techniques along with analyzing at a microscopic level using a slit lamp to detect keratoconus.
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A slit lamp examination can reveal keratoconus. A specialist typically o b s e r v e s f o r t h e f o l l o w i ng ng s i g n s o f k e r a t o c o n u s w h e n p e r f o r m i n g t h i s examination:
Corneal thinning
A p i c a l s c a r r i n g – a p i c a l s c a r r i n g i s t h e s c a r r i n g o f t h e a p e x o f t h e cone)
V o g t ’ s s t r a i e – V o g t ’ s s t r a i e r e f e r s t o t h e s t r e s s l i n e s t h a t a r e c a u s e d
by thinning of cornea
F l e i s c h e r ’ s r i n g – T h e F l e i s c h e r ’ s r i n g i s a i r o n - c o l o r e d r i n g w h i c h
surrounds the cone The curvature of the cornea needs to be checked to confirm any development of keratoconus. This can be done by:
P e r f o r m i n g C o r n e a l T o p o g r a p h y – T h i s i s a n c o m p u t e r i z e d i n s t r u m e n t t h a t c a n m a k e a t h r e e d i m e n s i o n al i m a g e o f t h e c o r n e a
K e r a t o m e t r y – T h i s i n s t r u m e n t i s d e s i g n e d t o s h i n e s e v e r a l p a t t e r n s o f light onto the cornea. The pattern at which the light is reflected helps specialists determine the curvature and shape of the cornea.
T r e a t i n g K e r a t o co co n u s There are generally two ways of through which the effects of keratoconus on the vision can be corrected:
By Wearing Eye Glasses
By Wearing Contact Lenses
Eye Glasses During the early stages of Keratoconus, eye specialists may prescribe glasses in order to help the patient improve their vision. Eye glasses can reduce the v i s i o n p r o b l e m s t h a t a r e t y p i c a l l y e x p e r ie n c e d b y a p e r s o n s u f f e r i n g f r o m keratoconus. An individual may experience problems with adjusting to their new pair of glasses if:
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they have never worn eye glasses previously;
a new, stronger prescription of glasses has been given to them than t h e o n e t h e y w e r e p r e v i o u s ly ly w e a r i n g
keratoconus has progressed in its intensity and has distorted the vision to a greater extent
As the keratoconus continues to distort the natural shape of the cornea, the vision will deteriorate and the person will need to keep changing their eye glasses. Glasses can help only up till a certain point, after w hich they are rendered useless by the severely distorted cornea. One of the symptoms of keratoconus is an increased sensitivity to light . This problem can be reduced by getting tinted prescription eye gl asses, by use of s u n g l a s s e s a n d h a t s t o m i n i m i z e e x p o s u r e t o l i g h t a s m u c h a s p o s s i b le le .
Contact Lenses As of now, contact lenses are a standard way of dealing with Keratoconus:
Contact lenses can restore vision beyond the limit of eye glasses. A lot of individuals who have Keratoconus spend several years using contact lenses.
Typically, special types of contact lenses are required for people with K e r a t o c o n u s . T h e s e l e n s e s a r e c a n o n l y b e f i t t e d a t a n e y e c l i n i c. c.
These special lenses require precise and careful fitting due to the highly abnormal shape of the cornea.
Individuals who have Keratoconus have to face similar issues as those people who use contact lenses to correct their vision. Nonetheless, some addit ional issues are faced by them because of their eye disorder:
The eyes of people with keratoconus are generally much more sensitive.
These people are more prone to allergies; this can lead to itching in the eyes.
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These people are also more susceptible to eye infections as wel l as other eye disorders.
Use of normal contact lenses can cause severe damage to their e yes.
Ordinary lens cleaning solutions can cause permanent eye damage to people with Keratoconus. This is because these solutions have no t been specially designed for them and thus can cause allergic r eactions.
Types of Contact Lenses for People with Keratoconus Individuals with keratoconus require specially designed contact lenses. These contact lenses are designed in a way that makes the curve at the front spherical in shape. This design not only helps in reducing the amount of restoration, but also acts as a solution to other eye disorder s such as myopia, hyperopia a n d a s t i g m a t i s m. m. Some types of contact lenses are as follows:
Soft Lenses
Hard Lenses
Combination Lenses
Scleral Lenses
Tinted Lenses (to cater for light sensitivity)
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Retinal Detachment
Figure 10 This is how a person would see when the retina begins to detach as a result of retinal tears.
The retina is located at the back of the eye and is covered with light s e n s i t i v e c e l l s t h a t a r e r e s p o n s i bl bl e f o r g e n e r a t i n g e l e c t r i c a l i m p u l s e s a s a result of the light that is focused onto them by the pupil and the lens. These impulses are sent to the brain through the optic nerve. When the retina separates itself from the back of the eye , retinal detachment is said to occur. This is an extremely serious condi tion a nd can lead to blindness if the retina completely detaches itself from the back of the eye.
Causes of Retinal Detachment Retinal detachment begins when small cuts in the retina give way to fluid from the eye. This liquid seeps through the cuts and begins to separate the retina from the tissue to which it was connected.
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To better understand how the retina gets detached, image a poster that has been glued to the wall. Now let us consider that the poster has been cut slightly, and this cut has exposed the wall behind the poster. If w ater is poured through this cut, the water will eventually separate the poster from the wall by dissolving the glue; this is precisely how a retina gets separated from the underlying tissues. Retinal tears can also be caused by the shrinking of the vitreous. The vitreous is a thick substance that resembles a jelly and it keeps the eyeball steady. Once the vitreous begins to shrink, the retina is pulled away from the back.
Symptoms of Retinal Detachment Around 1 in 10000 people are affected by r etinal detachment to varying degrees. This risk of retinal detachment increases as the age of an individual increases. Here are the symptoms of retinal detachment:
Blurred vision
Appearance of bright light at the corners of a person’s field of view
Appearance of dark areas in the field of view of a person
Loss of vision
Risk Factors Some individuals have a greater chance of experiencing retinal detachment than others. Some of the factors that increase the chances of suffering from retinal tearing include:
F a m i l y H i s t o r y – I f r e t i n a l d e t a c h m e n t p r o b l e m r u n s i n t h e f a m i l y , t h e n the newer generations have a greater chance of suffering the sa me
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M y o p i a ( S h o r t s i g h t e d n e s s ) – P e o p l e w h o h a v e m y o p i a a r e m o r e l i k e l y to experience a retinal tear.
P r i o r C a t a r a c t S u r g e r y – I f a n e y e s u r g e r y h a s b e e n p e r f o r m e d , t h e n the risk is higher as well.
E y e I n j u r i e s – E y e i n j u r i e s i n c r e a s e t h e l i k e l i h o o d o f s u f f e r i n g f r o m this condition
I n c r e a s i n g A g e – O l d e r p e o p l e h a v e a n i n c r e a s e d c h a n c e o f r e t i n a l detachment
du a l h a s h a d r e t i n a l d e t a c h m e n t P r i o r R e t i n a l D e t a c h m e nt n t – I f a n i n d i v i du in one eye, then it is very likely that the other eye will experience the same.
Complications of Retinal Detachment Retinal detachment is a serious eye illness, and it should never be left untreated. Doing so will have dire consequence on a person’s vision and will
eventually become the cause of their blindness. Some other complications may be as follows:
B l e e d i n g i n t h e e y e b a l l – t h i s b l e e d i n g c a n c l o u d t h e v i t r e o u s
P r e s s u r e b u i l d - u p i n s i d e t h e e y e b a l l – I n c r e a s i n g i n t r a o c u l a r p r e s s u r e can lead to other complications such as glaucoma.
F o r m a t i o n o f C a t a r a c t – T h e r e i s a h i g h e r c h a n c e o f a c a t a r a c t f o r m i n g
Treatment for Retinal T ears and Detachment R e t i n a l t e a r s c a n l e a d t o a r e t i n a l d e t a c h m e n t. T h e r e a r e t w o w a y s t h r o u g h which retinal tears can be healed, and they are as follows:
L a s e r S u r g e r y – A l a s e r c a n b e u s e d t o b u r n t h e r e t i n a a n d c a u s e i t t o produce scar tissue. This tissue can help in anchoring the reti na to the back of the eye
C r y o p e x y – A c r y o p r o b e i s a n e x t r e m e l y c o l d p r o b e t h a t c a u s e s t h e retina to generate scar tissue. The tissue ca n seal the tear and help keep the retina from detaching.
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If retinal detachment has already occurred, then surgery is the only option to get it back in place before permanent damage is done. H e r e a r e t h e t y p e s o f s u r g i c a l p r o c e d u r e s t h a t c a n b e c a r r ie d o u t f o r reattaching the retina:
P n e u m a t i c R e t i n o p l e xy x y – T h i s i s t h e s i m p l e s t t y p e o f s u r g e r y t o r e p a i r t h e d e t a c h e d r e t i n a . H o w e v e r , i t i s n o t s u i t e d t o e v e r y i n d i v i du a l . I n this procedure, the surgeon injects a gas bubble into the vitre ous, while the tears are sealed with a laser or cryopexy. The injected bubble presses upon the retina to put it flat against the wall. I t is i m p e r a t i v e t h a t t h e h e a d b e k e p t i n a p o s i t i o n a s i n s t r u c te te d b y t h e surgeon after the surgery.
S c l e r a l B u c k l i n g – T h i s p r o c e s s a l s o m a k e s u s e o f c r y o p e x y t o h e a l t h e retinal tears. Once that has been done, the fluid below the ret ina is drained out and a piece of silicone rubber is sewn the eye’s outer wall. This ‘buckle’ remains in position permanently even after the tears have
been sealed.
Vitrectomy Surgery - Vitrectomy surgery is carried out under a microscope. The vitreous is removed by the surgeon and any tears that may be present are treated using laser or cr yopexy (see treatment of retinal tears above). Once this has been done, the ey e is filled with silicone oil or gas. The silicone oil is eventually removed after several months. However, in some cases, the surgeon may de cide to leave the oil inside forever.
Some complications can follow depending on the type of surgery performed. These complications can result in:
Formation of cataract
Development of glaucoma
Severe infection
B l e e d i n g i n t h e v i t r e o u s c a v i t y ( H e m o r r h a ge )
Loss of vision
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Eye Floaters
Eye floaters appear in a person’s field of vision as a r esult of condensation or deposits in the vitreous jelly. These are ‘floating spots’, as commonly
described by people who see them whenever they look about. These floaters may be present in only one or both eyes.
W h y D o E y e F l o a t e r s A p p e ar ar ? It is the f unction of the cornea and the lens to focus the incoming light onto the retina. It is this light that causes the light-sensitive cells to generate electrical impulses which are sent to the brain through the optic nerve for processing. The light which passes through the retina has to go through a jelly-like material called the vitreous humor. From the time of birth up till
t h e e a r l y c h i l d h o o d y e a r s , t h i s s u b s t a n ce ce i s absolutely clear; however, as the person gr ows up, deposits, strands or even liquid pockets begin developing within this substance. The floating particles w h i c h p e o p l e s e e a r e t h e s h a d o w s o f t h e s e d e p o s i t s. s. W h e n a p e r s o n m o v e s t h e i r e y e s i n a n y d i r e c t i o n – w h e t h e r s i d e t o s i d e o r u p a n d d o w n – t h e s e p a r t i c l e s t e n d t o s h i f t t h e i r p o s i t i o n w i t h i n t h e e y e a n d this is precisely what makes the shadows move or appear as if t hey are ‘floating’.
C h a r a c t e r i s t i c s o f E y e F l o a t e rs rs Here are some of the characteristics of eye floaters:
Eye floaters can be of numerous shapes, ranging from tiny flecks, bubbles or webs to O-shaped strands.
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They are more obvious when a person focuses on a li ght colored area (sky, for example).
These eye floaters tend to move along with the movement of the eyes, with a slight lag, however.
What do they indicate? In most cases, the eye floaters are benign and pose no threat to the well being of an individual. People eventually get used to seeing them and simply ignore them. However, the floaters can be an indication of a more serious underlying condition. This is especially true if the number of floaters suddenly incr eases, then they can be an indication of:
Retinal tear
Retinal detachment
Bleeding in the eye
Eye tumor
Eye diseases
Eye injury
Diabetic retinopathy
If a person notices the following changes, a visit to an eye specialist becomes vital. 1. The eye floaters increase in number over time, more importantly if there are sudden changes 2. Flashes of light or any kind of loss in vision is experienced besides eye floaters 3. There is pain present alongside eye floaters 4. Eye floaters develop following an eye surgery
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Diabetic Retinopathy Retinopathy is an eye disease that affects the retina of the eye. It i s quite c o m m o n i n p e o p l e w i t h d i a b e t e s , a n d t h e y o f t e n d e v e l o p r e t i n o p a t h y. y. T h i s c o n d i t i o n c a n l e a d t o a s i g n i f i c an an t d e c r e a s e i n a p e r s o n ’ s v i s i o n , s o m e t i m e s
to an extent that they become blind. I t b e g i n w h e n t h e b l o o d v e s s e l s i n s id e a n e y e b e c o m e s w e a k e r . T h i s c a u s e s blood and other types of fluid to leak onto the retina. If this fluid seeps out i n t o t h e m i d d l e o f t h e e y e , t h e n b l u r r e d v i s i o n w i ll ll r e s u l t . Due to the fact that this retinal disease is caused by diabetes, it has a close link with the blood sugar levels of a person. If these levels r emain at a high level, this condition will continue to deteriorate . This condition may also cause the development of new blood vessels that are extremely fragile and prone to leaking, thus further worsening the situation. I f t h e s e n e w b l o o d v e s s e ls ls r u p t u r e , t h e y c o u l d l e a k b l o o d i n t o t h e c e n t e r o f t h e e y e a n d c a u s e c h a n g e s i n t h e v i s i o n a l o n g w i t h f o r m a ti o n o f s c a r t i s s u e . The scar tissue will, in turn, pull upon the retin a and detach it from the walls of the eye, leading to a retinal detachment (see page 67 of this book for more information). Another adverse effect of retinopathy on the eye is the swelling of macula. T h e m a c u l a i s l o c a t e d a t t h e m i d dl dl e o f t h e r e t i n a . W e u s e t h e m a c u l a t o appreciate the fine details, recognize faces and so on. S w e l l i n g o f m a c u l a u l t i m a t e l y l e a d s t o b l i n d n es es s .
Causes of Diabetic Retinopathy The main reason behind development of retinopathy is an inability to keep blood sugar levels under contr ol. High blood sugar levels can severely damage blood vessels in the re tina, thereby setting up the destructive chain of events discussed above.
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Symptoms of Diabetic Retinopathy I t t h e m a j o r i t y o f c a s e s , n o o b v i o u s s y mp mp t o m s o f d i a b e t i c r e t i n o p a t h y a r e present. The deterioration in vision is the main reason which leads to the discovery of retinopathy. However, by this time, the disease has advanced to a severe level. This is why it is essential that regular eye examinations be co nducted to d e t e c t a n y p o s s i b i l i t y o f a d e v e l o p i ng ng e y e d i s o r d e r .
T r e a t m e n t o f D i a b e t i c R e t i n o p a t hy hy T i l l d a t e , n o c u r e f o r d i a b e t i c r e t i n o p a t h y i s a v a i l a b l e. T h e r e a r e p r o c e d u r e s which can be carried out to prevent loss of vision. However, they have to be performed before the retina is severely damaged. T i m e l y d e t e c t i o n o f t h e d i s e a se se i s o n l y p o s s i b l e t h r o u g h r e g u l a r s c r e e n i n g e x a m i n a t i o n s , e s p e c i a ll ll y d u e t o t h e f a c t t h a t t h i s c o n d i t i o n d i s p l a ys n o o b v i o u s s y m p t om s u n t i l i t g e t s t o o l a t e . That being said, you should develop a habit of getting your eye s ex amined on a r e g u l a r b a s i s – m o r e f r e q u e n t l y a f t e r c r o s s i n g t h e a g e o f 4 0 .
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D r y E y e S y n d r o m e ( K e r a t o c o n j u n c ti ti v i t i s S i c c a ) To ensure maximum comfort for the eyes and to keep the vision at its best, nature has blessed us with a thin film of tears that coats our eyes. This coat helps in keeping the eye healthy. This thin film consists of three main layers, which are as follows:
Innermost Layer: This is the thinnest of all three layers and is a layer of mucin (mucus). This extremely thin layer of mucin is created by cells that are f o u n d i n t h e c o n j u n c t i v a. a. T h e p u r p o s e o f t h i s m u c i n i s t o h e l p t h e o v e r l a y i n g layer to spread consistently over the eye.
M i d d l e L a y e r : T h e m i d d l e l a y e r i s a l s o k n o w n a s t h e a q u e o u s l a y e r . T h i s i s t h e t h i c k e s t o f a l l t h e l a y e r s a n d i s t y p i c a l l y a n e x t r e m e l y d i l u t e d s a l tw a t e r solution. This watery layer is produced by the lacrimal glands that are l o c a t e d u n d e r t h e u p pe pe r e y e l i d s .
T h e p u r p o se se o f t h i s l a y e r is t o k e e p t h e
eye well-moistened and to keep out any dust or foreign objects that may get i n t o t h e e y e . G e n e r a l l y , a n y f l a w s i n t h e a q u e o u s l a y e r a r e r e s p o n s ib ib l e f o r leading to the dry eye syndrome.
Outer Layer: The outermost layer consists of an extremely thin layer of lipids. Lipids can be of fats or oils. The meibomian glands and Zeis glands are responsible for producing these lipids whose function is to redu ce evaporation of the aqueous layer that is found below. Any defects in this tear film lead to w hat we commonly call the dry eye s y n d r o m e ( D E S ) . T h i s s y n d r o m e a f f e c t s q u i t e a p e r c e n t a g e o f p o p u l a ti ti o n , most of the people that are affected by this disorder are above the age of 40 years. In the United States, it is estimated that somewhere between 25 to 30 million people are affected by dry eye syndrome. This condition can affect any person of any race and is found to be more widespread in women than in men.
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Causes of Dry Eye Syndrome Dry eye syndrome is a quite common type of eye disorder that leads to the following:
A d e c r e a s e i n t h e t e a r p r o d u c t i on o n – t h i s i s c a u s e d b y a r e d u c e d a b i l i t y of the tear glands to produce tears. This can be due to aging, any hormonal changes or due to a number of diseases associated with the autoimmune system, including, but not limited to Rheumatoid arthritis, lupus or Sjogren syndrome. There are quite a few medications th at have adverse effects on the eye, and we will cover them in detail in the next chapter. For now, you need to be aware of the fact that a n t i d e p r e s s a n t s , a n t i h i s t am am i n e s a n d n u m e r o u s o r a l c o n t r a c e p t i v e s a r e known to decrease the production of tears.
A n i n c r e a s e i n t e a r e v a p o r a t i o n – L o s s o f t h e a q u e o u s l a y e r d u e t o e v a p o r a t i o n i s n o r m a ll y d u e t o a r e d u c t i o n o f t h e o v e r l y i n g l i p i d l a y e r (recall that the lipid layer’s function is to reduce evaporation of the
aqueous layer)
Onset of an abnormality in production of lipids as well as the mucin (mucus) that is found in the layers of the tear
Evaporation of the aqueous layer can also result from a decreas e in the n a t u r a l r a t e o f b l i n k i n g . T h i s c a n l e a d t o t h e d r y e y e s y n d r o m e . R e d u c ti o n i n blinking can be due to the following: While performing activities such as reading, watching TV as well as those that require great amounts of attention, the rate at which we blink is considerably decreased. This reduction in blinking can lead to the evaporation of tears and to the dryness of eyes. T h e r e a r e a f e w c o n d i t i o n s s u c h a s B e l l ’ s p a l sy sy , o r t h e a f t e r e f f e c t s o f a
stroke, that can make it hard for a person to close their eyes. Again, this contributes to the evaporation rate of the tears. An abnormality in the production of mucus by the conjunctiva is also known t o b e a c o n t r i b u t or or t o t h e d e v e l o p m e n t o f d r y e y e s s y n d r o m e .
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This abnormal production can result due to numerous autoimmune diseases, f o r e x a m p l e c i c a t r i c i a l p e m p h i g o i d a n d S t e v e n s - J o h n so so n S y n d r o m e . T h e abnormality can also occur due to alkali burns to the eye. The anomaly is known to cause problems in the even spreading of tears over the eye, causing the eye to become dryer and in severe cases, damaged; this can occur even when ample quantities aqueous layer is present. The meubomian gland dysfunction leads to a reduction in the lipid layers. These glands are found below the upper eyelids and their function is to produce the lipid layer. If due to any reason, these glands bec ome blocked, the insufficient lipid layer can allow the aqueous layer to evaporate.
Symptoms of Dry Eye Syndrome A p e r s o n , w h o h a s t h e d r y e y e s y n d r o m e , w i l l e x p e r i e n c e t h e f o l l o w i ng ng symptoms:
Dry, scratchy or gritty eyes
A burning or itching sensation in the eyes
Redness in the eyes
Blurry vision
A feeling of having a foreign object in the eye
Increased sensitivity to light
The above symptoms generally increase in intensity in dry climates, windy and low humidity conditions - especially when the eyes have bee n used for prolonged duration. Another symptom that sometimes occurs as a result of the dry ey es syndrome is that intermitted, excessive tearing may occur. This happens when the eyes b e c o m e s o m e w h a t d r y , a n d t h e n a t u r a l m e c h a n i sm t h a t i s r e s p o n s i b l e f o r k e e p i n g t h e e y e s c o m f o r t a bl bl e a n d m o i s t , r e s p o n d s b y p r o d u c i n g l o t s o f t e a r s in an attempt to eliminate the irritation. Unfortunately, the eye is only capable of retaining a certain amount of tears, the rest are e xpelled and they pour down the cheeks. These tears are
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wasted, and as soon as the eyes become dry again, this process is repeated again. It becomes necessary that you see an eye specialist if the following is experienced:
Pain in the eyes (see page 35 for more details)
Excessive tearing
An itching or burning sensation in the eyes
Blurry vision
A feeling of having a foreign object in the eye
Heightened sensitivity to light
Redness of your eyes
Diagnosis and Treatment of Dry Eye Syndrome If you are experiencing the above s y m p t o m s , y o u r o p h t h a l m o lo lo g i s t will most probably be able to diagnose the syndrome. However, the following tests can help in revealing whether or not you’re suffering from this particular syndrome. A d e t a i l e d e y e e x a m i n a t i o n w i l l i n c l u de t h e f o l l o w i n g t e s t s :
Slit Lamp Test
T h e f r o n t o f t h e e y e s w i l l b e e x a m i n e d u s i n g a s p e c i a l m i c r o s c op e t h a t is called a slit lamp. Using this microscope, the thickness of your tear film as well as the amount is inspected.
Assessment of the tear break up time helps in determining the stability of your tear film.
The conjunctiva itself is examined to check its level of drynes s
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The cornea is examined to see whether the dryne ss caused any damage
Numerous colored dyes may be used during the test. They are as follows: Rose Bengal is a red dye that stains the conjunctiva as well as the cornea in
order to highlight cells that may be dead, or dying. This will help in finding those cells which are improperly protected by the tear film. Fluorescein is a yellow dye that is used to stain the cornea in order to see
where epithelial cells might have been worn away as a result of the reduction in the protective tear film. Lissamon Green is a green dye that can, similarly to the above two dyes, help
in locating and differentiating between healthy and abnormal cells in the eye.
Schirmer Tests The Schirmer tests are used to m easure the quantity of tears that are produced by the eyes. The end of a thin strip of paper is placed inside in lower eye lid. The paper is removed after duration of approximately a minute, and the amount of wetting is measured to find the amoun t of tears produced. A decreased wetting will indicate presence of the dry eye syndrome.
Other Tests A n u m b e r o f o t h e r t e s t s m a y b e p e r f o r m e d , d e p e n d i ng o n t h e r e s u l t s g a i n e d by the above tests: The salt content of the tears can be measured in order to assist in d i a g n o s i n g d r y e y e s y n d r o m e . T h i s o s m ol ol a r i t y t e s t i s a n e w t e s t t h a t h a s been developed precisely to assist in diagnoses of DES. I f t h e d o c t o r s u s p e c t s t h a t a u t o i m m u ne ne s y s t e m d i s e a s e s a r e b e h i n d t h e d r y eye syndrome, then a number of blood tests may be carried out t o confirm
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the possibility. These blood tests will also verify existence of differing a u t o a n t i b o di di e s t h a t m a y w e l l b e a s s o c i a t e d w i t h d r y e y e s s y n d r o m e . A biopsy of the salivary glands may be performed; however, this only h a p p e n s i n r a r e c a s e s . T h e s a l i v a r y g l a n d s a r e r e s p o n s i b le l e f o r p r o d u c i ng ng saliva. The lacrimal glands, on the other hand, produce tears. There are certain diseases that affect both of these glands. N o c u r e e x i s t s f o r d r y e y e s s y n d r o m e . D e p e n di di n g o n t h e s e v e r i t y o f D E S , s o m e e y e d r o p s o r a h u m i d i fi fi e r m a y b e r e q u i r e d t o m o i s t e n t h e a i r . I n extreme cases, surgery may be needed to treat the syndrome. There are artificial tears available as over-the-counter eye drops that help i n lubricating the eyes and relieve the symptoms of dry eyes syndr ome. It is best to use them if advised by an eye specialist.
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Chapter 5 Drugs Harmful to the Eye
Medical science has evolved in unprecedented ways over the last few decades. An umpteen number of drugs and medicine have been crea ted to fight the colossal number of diseases. These developments have paved way for a healthier society and there were certain diseases which were, up until now, labeled as being untreatable. These medicines have come with a price, however. Nothing in this universe is perfect, and the same applies to these drugs. Many of the drugs tha t are commonly consumed by us come with a set of side effects. These can range from being mere headaches or drowsiness, to some so severe that they can cause a person to become vulnerable to other diseases. In this chapter, we will look into those drugs t hat have an adverse effect on t h e e y e s . W e a i m t o i n c l u d e a l l t h e n e c e s s a r y i n f o r m a ti o n t h a t w i l l e m p o w e r
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you with the knowledge that will help you to become aware of any possible implications of using the drugs.
Acne Medication 1. Isotretinoin Generic Name: Isotretinoin B r a n d N a m e s : A c c u t a n e , A m n e s t e e m , C l a r a v i s , S o t r e t I s o t r e t i n o i n i s a p h o t o s e n s i t i zi zi n g d r u g t h a t i s u s e d t o t r e a t s e v e r e a c n e t h a t has not responded well to other kinds of treatment. Among the known very c o m m o n s i d e e f f e c t s o f I s o t r e t i n o i n o n e y e s i n c l u d e t h e f o l l o wi wi n g :
Blepharitis
Conjunctivitis
Dry Eyes Syndrome
Eye Irritation
However, in rare cases, the following may also result due to th e usage of isotretinoin:
Blurry vision
Sudden decrease in night vision
Color blindness
Cataracts
Keratitis
Papilloedma
Photophobia
2. Minocycline Generic Name: Minocycline Brand Names: Minocin
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Minocycline is a drug that is used to treat acne, as well as some other health disorders. It can lead to pigmentation of the sclera; however, it tends to g o a w a y w h e n t h e u s e o f d r u g i s d i s c o n t i n ue d .
Alzheimer's Medication 1. Cholinesterase Inhibitors Generic Name: Donepezil, Galantamine, Rivastigmine B r a n d N a m e : A r i c e p t , R e m i n y l , E x e l o n C h o l i n e s t e r a s e i n h i bi t o r s a r e o f t e n p r e s c r i b e d t o p a t i e n t s w h o a r e s u f f e r i n g from mild Alzheimer’s disease.
These inhibitors help in stopping the breakdown of acetylcholine (a neurotransmitter that helps in memory and thinking skills) due to Alzheimer’s disease.
H o w e v e r , t h e y c a n c a u s e s u b c o n j un ). u n c t i v a l h e m o r r h a g e ( e y e h e m o r r h a g e ).
Antibiotics Antibiotics are used to treat numerous infections caused by bacteria. The antibiotics are powerful drugs that are use d to fight off bacterial infections. However, they tend to have a number of side effects associated with them. It is recommended that probiotics be used whenever consuming antibiot ics in order to minimize some of the side effects that result due to the consumption of the latter. Probiotics such as acidophilus or bifidus along with vitamin C can help do just that. Some antibiotics are known to increase a person’s sensitivity to light,
t h e r e b y i n c r e a s i n g t h e r i s k o f d e v e l o p i ng ng g l a u c o m a o r d r y e y e s y n d r o m e . Q u i t e a f e w t o p i c a l a n t i b i o t i c s c a n l e a d t o a n a l l e r g e n i c c o n j u n c t i v i t is is , w h i l e o r a l a n d i n t r a v e n o u s a n t i b i o ti ti c s a r e k n o w n t o b r i n g a b o u t s o m e f o r m o f distortion in vision.
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1. Fluoroquinolones Generic Name: Ciprofloxacin, levofloxacine Brand Name: Cipro, Zoxan, Proquin; Levaquin, Cravit F l u o r o q u i n ol ol o n e s ( c i p r o f l o x a c i n a n d l e v o f l o x a c i n e ) a r e a m o n g t h e m o s t c o m m o n l y p r e s c r i b e d o r a l a n t i b i o t i c s d u e t o t h e i r c o m p a r a t i v el el y b e n i g n safety profile. However, according to researchers, there is an increased risk of retinal detachment following the use of these antibiotics. I t i s e s t i m a t e d t h a t f o r e v e r y 2 5 0 0 p e o p l e t h a t u s e f l u o r o q u i n ol ol o n e s , 1 person will suffer from a retinal detachment.
2. Synthetic Penicillin G e n e r i c N a m e : A m o x i c i l l i n , A m p i c i l l i n B r a n d N a m e : A m o x i l , T r i m o x , M o x i l i n , M o x a t a g ; O m n i p e n , P r i n c i p e n , Totacillin-N, Omnipen-N
S y n t h e t i c p e n i c i l l i n s s u c h a s a m o x i c i l l i n a n d a m p i c i l l in a r e k n o w n t o h a v e side effects that cause mild redness of the eye, dry eyes and itching. In some of the cases that were observed, they were seen to cause hamorrhages of blood vessels in both the conjunctiva and the retina. They can contribute to t h e d e v e l o p m e n t o f a l l e r g e n i c c o n j u n c t i v i t is ( g o t o p a g e 6 8 o f t h i s b o o k f o r m o r e i n f o r m a t i o n o n C o n j u n c t i v i t i s) .
3. Terbinafine G e n e r i c N a m e : A m o x i c i l l i n , A m p i c i l l i n Brand Name: Lamisil, Lamisil AT Lamisil is an antifungal medication that is used to treat fingernail fungus. It c o m e s u n d e r t h e c a t e g o r y o f p h o t o s e n s i t i zi zi n g d r u g s a n d i n c r e a s e s a p e r s o n ’ s s e n s i t i v e n e s s t o l i g h t . I t s k n o w n s i d e e f f e c t s i n c l u d e a r i s k o f d e v e l o p i ng ng cataracts and macular degeneration.
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4. Tetracycline Generic Name: Tetracycline Brand Name: Sumycin, Achromycin V, Panmycin, Sumycin 250 Tetracycline is an antibiotic that is used to fight a number of bacterial infections ranging from urinary tract infections to Chlamydia and numerous others. Tetracycline has similar effects on eyes to that caused by synthetic p e n i c i l l i n s. s. U s e o f t h i s a n t i b i o t i c m a y c a u s e i n c r e a s e d s e n s i t i v i t y t o l i g h t a n d cause the vision to become blurry. The chances of developing allergic conjunctivitis are also increased.
Antidiuretics Diuretics are drugs used to increase the amount of urine produced by the kidneys and increase the excretion of sodium and other electrolytes (Karch, 2 0 0 3 ) . A n t i D i u r e t i c s , o n t h e o t h e r h a n d , a r e d r u g s t h a t h e l p i n c o n t r o l l i ng the body’s balance of w ater by reducing urination.
Any misuse of these drugs can lead to upsetting the chemical balance along w i t h t h e b a l a n c e o f f l u i d s i n t h e w h o l e o f t h e b o d y , i n c l u d in g t h e e y e s . T h i s u p s e t c a n l e a d t o d e v e l o p me me n t o f g l a u c o m a .
Antihistamines Generic Name: acrivastine, alimemazine, cetirizine, chlorphenamine, clemastine, cyproheptadine, desloratadine, fexofenadine, hydroxyzine, ketotifen levocetirizine, loratadine, mizolastine,promethazine.
Brand Name: Numerous A n t i h i s t a m i n e s a r e c o m m o nl nl y u s e d t o t r e a t a l l e r g i e s r e s u l t i n g f r o m a n u m b e r of things, such as hay fever (rhinitis), hives (urticaria), itching (pruritus) and as a result of insect bites and stings.
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They can also be utilized for reducing nausea and vomiting, bes ides being u s e d a s a n e m e r g e n c y t r e a t m e n t o f a n a p h y l a x i s – w h i c h i s a s e v e r e a l l e r g e n i c reaction. A n t i h i s t a m i n e s a r e k n o w n t o h a v e s e v e r a l e f f e c t s o n t h e e y e s , i n c l u d i ng ng :
I n c r e a s e d p h o t o s e n s i t i v i t y ( s e n s i t i v e n es s t o l i g h t )
Dryness of eyes, leading to the dry eye syndrome
Increased risk of cataracts
Can cause pupils to become asymmetrical in size
A n t i h i s t a m i n e s c a n b e e s p e c i a l ly ly h a r m f u l t o t h o s e p e o p l e w h o h a v e a n g l e closure glaucoma (see page 47 for more details on the types of glaucoma). The use of antihistamines by such people can set off an attack of angle closure glaucoma and cause blurry vision, redness of the eye, halos as well a s e y e p a i n . S u c h a n a t t a c k i s a n e m e r g e n c y c o n d i t i o n. A n t i h i s t a m i n e s h a v e p h o t o s e ns ns i t i z i n g p r o p e r t i e s . T h i s m e a n s t h a t t h e y increase a person’s sensitivity to light (especially sunlight). These drugs
a b s o r b t h e i n c o m i n g l i g h t a n d c a r r y o u t a p h o t o - c h e m i c al al r e a c t i o n t h a t c a n modify tissues. This can lead to not only cataracts, but also macular degeneration.
Anti-Anxiety Medication Generic Name: Alprazolam, Clonazepam, Diazepam, Lorazpam B r a n d N a m e : X a n a x ; K l o n o p i n ; V a l i u m ; A t i v a n S o m e m e d i c i n e s c a n r e l i e v e a f e w s y m p t o m s o f a n x i e t y – s u c h d r u g s a r e referred to as anti-anxiety drugs. Numerous types of such medic ines are a v a i l a b l e , i n c l u d i n g t h e t r a d i t i o n a l d r u g s s u c h a s b e n z o d i a ze ze p i n e s . M o r e conventional options include antidepressants and beta blockers. These medicines can be no doubt very effective; however, they s hould not be t h o u g h t o f a s b ei n g a c u r e .
T h e y o n l y p r o vi d e a t e m p o r a r y r e li e f , a n d a m o r e
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permanent solution should be sought to avoid becoming dependent on these drugs. A n t i - a n x i e t y d r u g s a r e a l s o c o m m o n l y k n o w n a s t r a n q u i li l i z e r s . T r a n q u i li li z e r s are photosensitizing drugs. This means that they increase a person’s s e n s i t i v i t y t o l i g h t ( e s p e c i a ll ll y s u n l i g h t ) . T h e s e d r u g s a b s o r b t h e i n c o m i n g light and carry out a photo-chemical reaction that can modify tissues. This can lead to macular degeneration and development of cataracts.
Arthritis Medications 1. Hydroxychloroquine Sulfate Generic Name: Hydroxychloroquine Sulfate Brand Name: Plaquenil H y d r o x y c h l o r o q ui n e i s a n a n t i - m a l a r i a l d r u g t h a t i s u s e d i n t h e t r e a t m e n t o f a r t h r i t i s t o r e d u c e t h e i n f l a m m a t i o n. n. I t i s k n o w n t o h a v e s o m e s e r i o u s s i d e effects that affect the eyes. The first and foremost is the toxicity in the eye. Eye toxicity is generally calculated based on a person’s height and weight.
Toxicity from the use of this drug affects two distinct areas of the eye: the macula and the cornea. T h e c o r n e a c a n b e a f f e c t e d b y V o r t e x k e r a t o p a t h y, y, w h i c h i s c h a r a c t e r i z e d b y corneal epithelial deposits. This condition, however, is revers ible once the drug intake has been ceased. The effects on macula are serious, nevertheless. I t can lead to retinopathy; which, in its advanced stages, can considerably reduce visual acuity.
Asthma Medication 1. Corticosteroids Generic Name: Prednisone Brand Names: Deltasone, Meticorten, Orasone, Prednicot, Sterapred
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Prednisone is a corticosteroid that is used for treating asthma , be sides numerous other conditions. Prednisone is known to increase a person’s risk
of developing eye disorders such as gl aucoma and cataracts. The risk of glaucoma is increased because of the elevated intraocular pressure (eye pressure) as a result of the use of corticosteroids.
Birth Control The chances of suffering from dry eye syndrome are increased as a result of consuming birth control pills. Contraceptives that are consumed orally are k n o w n t o l e a d t o a n u m b e r o f e y e d i s o r d e r s , i n c l u d i n g e l e v a t i n g i n t r a o c u l ar pressure, causing headaches, changes in vision, and causing the optic nerve to swell. Retinal vascular problems can also be caused by use of birth control pills. Some pills can also result in inducing an increased sensitivity to light, leading to a chemical modification of tissues that can lead to cataracts or macular degeneration. Birth control pills are also known to cause disturbances in a person’s color vision.
P a r k i n s o n ’ s D i s e a s e M e d i c a t i o n U s e o f c e r t a i n m e d i c a t i o n f o r P a r k i n s o n ’s d i s e a s e c a n c a u s e b l e p h a r o s p a s m
o r i f a p e r s o n a l r e a d y h a s t h i s c o n d i t i o n, n, i t c a n f u r t h e r a g g r a v a t e i t . B l e p h a r o s p a s m i s a b n o rm rm a l t w i t c h i n g o f t h e e y e l i d s t h a t l e a d s t o e x c e s s i v e b l i n k i n g , d r y n e s s o f t h e e y e s a n d i n c r e a s e d s e n s i t i vi t y t o t h e s u n o r a n y source of bright light.
Blood Pressure Medication There are a number of medications available that are used to co ntrol high blood pressure. These are known as antihypertensives. The type of medication your doctor will prescribe for you will depend on how high your blood pressure is.
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N o n e t h e l e s s , r e g a r d l e s s o f t h e t y p e o f m e d i c a t i o n , a n t i h y p e r te te n s i v e s a r e known to excrete excess fluid from blood vessels in an a ttempt to bring down the blood pressure. The re duction in the amount of fluid generally leads to dry eyes (dry eyes syndrome), increased sensitivity to light, blurred vision or even double vision in some cases. Beta blockers are also commonly used to reduce blood pressure by altering the kidney’s rate of producing rennin – a protein that is responsible for
releasing angiotensin II. Angiotensin II is a powerful blood vessel constrictor that makes it difficult for the blood to flow through arteries, thereby r aising the pressure. This constrictor also releases hormones that cause an increase in the amount of fluid that is present in the blood (water retention). A common drug that is used to lower the blood pressure is called Clonidine ; extended use of this drug can cause permanent damage to the retina.
Blood Thinning Medication Generic Name: Heparin, Coumadin, Anisindione and many others. Blood thinners are prescribed to people who have some sort of h eart or blood vessel ailment. It can also be prescribed if they have a poor flow of blood to the brain. Blood thinners greatly reduce the chances o f a stroke or a heart attack by preventing the formation of blood clots in the blood vessels (arteries and veins). They are also used in the following conditions:
Heart valve surgery
Atrial fibrillation (abnormal heart rhythm
Congenital heart defects
T h e r e a r e t w o m a i n t y p e s o f b l o o d t h i n n e r s : A n t i c o a g ul ul a n t s a n d a n t i p l a t e l e t s . A n t i c o a g ul ul a n t s i n c r e a s e t h e t i m e i t t a k e s f o r a b l o o d c l o t t o f o r m . O n t h e o t h e r h a n d , a n t i p l a t el el e t d r u g s p r e v e n t p l a t e l e t s f r o m c l u s t e r i n g together.
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H o w e v e r , t h e s e b l o o d t h i n n e r s c a n l e a d h e m o r r h a g i ng i n t h e e y e .
Cancer Medication Generic Name: Fluorouracil (5-FU), Tamoxifen Fluorouracil (5-FU) is a drug that belongs to a class of chemot herapy drugs which we call anti-metabolites. Its purpose is to interfere with those cells t h a t m a k e D N A a n d R N A i n o r d e r t o s t o p t h e g r o w t h o f c a n c e r c e ll ll s . There are a great number of side effects of this drug; and the person using this needs to be monitored more if radiation and chemotherapy is being used to treat the cancer patient. This drug can close the tear drainage system of the eye, leading to eye tearing. Tamoxifen is a treatment prescribed to those undergoing breast cancer treatments. Crystalline deposits in both the retina and cornea can be deposited as a side effect of this medication.
Depression Medication Generic Name: Venlafaxine, Fluvoxamine, Paraxetine, Mirtazapine, Fluoxetine, Amitriptyline, Desipramine , Imipramine , Nortriptyline
Brand Name: Effexor; Luvox; Paxil; Prozac Antidepressants are used to help people with several major depressive disorders, including:
anxiety disorders,
attention-deficit hyperactivity disorder (ADHD),
dysmenorrhoea,
dysthymia,
eating disorders, chronic pain,
migraines,
neuropathic pain and, in some cases,
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obsessive compulsive disorder,
snoring,
substance abuse and sleep disorders
H o w e v e r , l i k e a l l m e d i c i n e , a n t i d e p r e s s a nt s a l s o h a v e s o m e d a n g e r o u s s i d e effects, and some of them are as follows:
Venlafaxine i s a n a n t i d e p r e s s a n t t h a t i s p r e s c r i b e d t o p e o p l e w i t h
d e p r e s s i o n p r o b l e m s . O n e o f i t s s i d e e f f e c t s i n c l u d e s t h e p o s s i b il il i t y o f optical nerve damage as well as glaucoma.
Venlafaxine can also lead to hemorrhage in the eye
M i r t a z a p i n e i s y e t a n o t h e r a n t i d e p r e s s an t f r e q u e n t l y p r e s c r i b e d t o
people with depression. It also can lead to damaged optic nerve and glaucoma.
em s i n t h e e y e s , i n c l u d i n g P r o z a c ( f l u o x e t i n e ) c a n c a u s e v a r i o u s p r o b l em double vision, blurry vision, dry eyes syndrome, eye pain, bleph aritis ( e y e l i d i n f e c t i o n ) , c a t a r a c t s , g l a u c o ma , p t o s i s a s w e l l a s i r i t i s .
Tricyclic antidepressants, such as amitriptyline, desipramine, imipramine, and nortriptyline are known to cause several problems
with the vision of a person, including causing loss of the ability to focus closer objects. To sum up, anti-depressants can cause the following eye and vision problems:
Double Vision
Dilated Pupils
Blurred Vision
Glaucoma (angle closure glaucoma)
Cataracts
Blepharitis (eye lid infection)
Ptosis (Drooping eye lids)
Iritis (Inflammation of iris)
Optic Nerve Damage
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Diabetes Medication Generic Name: thiazolidinediones, pioglitazone , rosiglitazone Diabetes refers to a gr oup of metabolic diseases in which a person has high blood glucose due to a number of reasons:
1. Inadequate production of insulin, 2. Lack of response from body’s cells to insulin; 3. Both of the above. Medication for diabetic people comes in numerous forms, includi ng oral and as injectables. Diabetes is a disease that makes a person very vulnerable to al l kinds of d i s e a s e s , i n c l u d i n g t h e e y e a i l m e n t k n o w n a s D i a b e t i c R e t i n o p a th t h y – w h i c h basically results when the blood sugar levels cannot be kept down to normal levels. N u m e r o u s o r a l d r u g s w h i c h a r e u s e d f o r d i a b e t e s a r e p h o t o s e n s i t i z i ng . A p h o t o s e n s i t i z i ng ng a g e n t ( f o u n d i n s u c h a d r u g ) i s o n e w h i c h i s e x c i t e d b y specific wavelengths of light. Consuming this drug increases a person’s s e n s i t i v i t y t o l i g h t ( e s p e c i a ll ll y s u n l i g h t ) ; t h e s e t h e n a b s o r b t h e i n c o m i n g l i g h t and carry out a photo-chemical reaction which alters the body’s tissues. This leads to macular degeneration as well as ca taracts. T h o s e p e o p l e w h o a r e p r e s c r i b e d c e r t a i n d r u g s k n o w n a s t h i a z o l i d i n e d i o ne ne s , p i o g l i t a z o n e a n d r o s i g l i t a z o ne h a v e a n i n c r e a s e d r i s k o f d e v e l o p i n g m a c u l a r edema by three to six times.
Dilating Eye (Pupils) Medicine Mydriatics is the term that refers to dilating eye drops. These drops are used to either dilate or enlarge the pupils of a person’s eye so that an eye
specialist can see the inside of an eye during an examination. These dilating drops work in three different ways as follows:
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le f o r 1 . T h e y c a n t e m p o r a r i l y p a r a l y z e t h o s e m u s c l e s t h a t a r e r e s p o n s i b le reducing the size of the pupil.
2. They can stimulate the muscles whose function is to make the iris become wider.
3 . T h e y c a n p r e v e n t t h e p u p i l i t s e l f f r o m a d j u s t i n g t o f o c u s – t h i s i s c a l l e d a c c o m m o d a t i on on . Once the pupils have been dilated, an eye specialist can them u se his or her instruments in order to analyze the eye’s lens. The retina can also be seen,
and so can the optic nerve. Simply put, dilating the pupil give s an eye specialist a clear view of the complete inner w orkings of your eye. The downside, however, is that these drops significantly increase the risk of developing an angle closure glaucoma and can contribute to optic nerve damage.
Erectile Dysfunction (ED) G e n e r i c N a m e : t a d a l a f i l , v a r d e n a f i l h y d r o c h o l o r i de d e , s i l d e n af af i l c i t r a t e Erectile dysfunction is a type of male sexual dysfunction that is common among a lot of men. It i s said to occur when a m an experiences problems in g e t t i n g a n e r e c t i o n , a s w e l l a s k e e p i n g o n e. I t i s s a i d t o g e t w o r s e w i t h a g e ; however, it is not considered to be a part of the aging process. The use of the drugs for treating erectile dysfunction can have some severe s i d e e f f e c t s o n t h e e y e s . S u d d e n l o s s o f v i s i o n c a n o c c u r , e s p e c i a ll y i n people who have previously had a heart attack.
Heart Medications Generic Names: Amiodarone, Digoxin, Pentoxifylline Numerous types of heart medication are available for a wide ran ge of cardiac-related issues. A m i o d a r o n e i s o n e t h a t i s k n o w n t o c a u s e c e r t a i n c h a n g e s t o t h e c o r n e a . I t
can create a w horl-like pattern on the surface of the cornea. However, this
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d i s a p p e a r s w h e n a p e r s o n q u i t s u s i n g t h i s m e d i c a t i o n. n . T h i s p a t t e r n c a u s e s n o apparent changes in a pe rson’s vision. Digoxin is a drug that is used by a person experiencing heart failure or
i r r e g u l a r i t i e s i n t h e h e a r t . T h i s d r u g i s k n o w n t o i n c r e a s e p h o t o s e n si t i v i t y (sensitiveness to light), thus leading to halos, glare and a yellowish tint in a person’s vision. Light flashes, blind spots and changes in color vision can
also be expected. Pentoxifylline is used to help in improving the circulation throughout the
human circulatory system. On the downside, it has caused, and can cause, hemorrhaging in the eye in some people. A link has been found between use of amadarone and optic neuritis (inflammation of the optic nerve). This is why it is essential for people using this drug to have regular eye examinations throughout the course of the drug.
High Cholesterol Medication Generic Name: Simvastatin, Astrovastatin calcium B r a n d N a m e : Z o c o r ; L i p i t o r Persistent high cholesterol levels can lead to a stroke or a he art attack. Statins are a group of medicines that are frequently used to treat high
cholesterol levels. Simvastatin can lead to optic nerve damage as well as glaucoma. The use of
these drugs increases the chance of developing a cataract by 27 per cent.
Hormone Replacement Androgen and Estrogen are natural hormones; their replacement by synthetic o n e s c a n l e a d t o c l o t t i n g o f b l o o d a n d r e d u c e d c i r c u l a t i on on o f b l o o d i n t h e eyes. Replacing the Estrogen hormone can also cause blespharospasm ( u n c o n t r o ll l l e d e y e t w i t c h i ng ng )
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Inflammation NSAID or Non-Steroidal Anti-Inflammatory Drugs consists of a family of drugs t h a t a r e u s e d t o r e d u c e i n f l a m m a t i o n. T h e r e s i d e e f f e c t s o n e y e s a r e numerous, and use of these drugs can cause:
Dry Eye Syndrome
Cataracts
Retinal Hemorrhages
T h e N S A I D s a r e a l s o p h o t o s e n s i t i zi n g a n d c a n m a k e a p e r s o n m o r e susceptible to cataracts and macular degeneration. These drugs can also cause damage to the optic nerve.
Insomnia G e n e r i c N a m e : B e n z o d i a z ep e p i n e s ( A l p r a z ol ol a m , C l o n a z e p a m , C l o r a z e p a m , D i a z e p a m , F l o r a ze z e p a m , L o r a z e p a m , Mi M i d a z o l a m , O x a z e p a m , T e m a z e pa pa m , T r a z o l a m , Z a l e p l o n Z o l p id id e m , Z o p i c l o n e )
B e n z o d i a z e p i n e s a r e c o m m o n l y p r e s c r i b e d t o p e o p l e w h o c o m p l ai ai n o f i n s o m n i a . T h i s g r o u p o f d r u g s i s k n o w n t o c a u s e b l e p h a r o sp sp a s m ( e y e twitching) and weakening of the ability to concentrate and memorize.
Malaria Medication Generic Name: Chloroquine, Quinacrine, Hydroxychloroquine Anti-malarial drugs such as those named above are known to cause several changes in the cornea of the eye. A person may experience symptoms such as glare, halos and have an increased sensitivity to light. In mos t cases, these d o n o t c a u s e a r e d u c t i o n i n t h e v i s u a l a c u i ty o f a p e r s o n . Chloroquine can, however, cause some serious problems. In some people, it
c a n l e a d t o r e t i n a l d e t a c h m e n t ( l e a d i n g t o b l i n d n e s s) , o p t i c n e r v e degeneration, reduction in the color vision and blurred vision. These effects depend on the duration the medication was consumed for.
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Quinine, if used by pregnant women, may cause an under-developed optic
n e r v e i n t h e f e t u s l e a d i n g t o t h e b i r t h o f a c h i l d w i t h u n d e r - d e v e l o p e d v i si o n system.
Pain Relief Medication Even the simplest of pain relief medication can have adverse ef fects on the eyes. Aspirin, which is an antiplatelet drug, can increase the bleeding of the eye and this is precisely why eye surgeons may recommend quitti ng use of aspirin a few days prior to the surgical procedure . The NSAID family (Non-Steroidal Anti-Inflammatory Drugs) has nu merous side e f f e c t s i n c l u d i n g a n i n c r e a s e d r i s k o f d e v e l o p i ng ng c a t a r a c t s , m a c u l a r degeneration, dry eyes syndrome, and even retinal hemorrhages i f the drug is used for extended periods of time. Misusing (or overuse) of the drugs which are considered by some to be ‘ h a r m l e s s ’ c a n a c t u a l l y d a m a g e t h e b o d y , i n c l u d i ng ng t h e e y e s . W h e n u s e d
e x c e s s i v e l y , t h e s e d r u g s c a n i n c r e a s e p h o t o s e n s i ti ti v e n e s s , l e a d t o d r y e y e s , corneal deposits and cataracts.
Psychiatric Medication Psychiatric medications are licensed psychoactive drugs that di rectly affect the chemical balance of the brain and the nervous system. These medications are prescribed to those people who have certain mental disorder s. Due to the fact that they have direct influence on the brain and the nervous system, they can cause some severe side effects in a number of people. Certain psychiatric medication can lead to pigmentation of the conjunctiva, cornea and the eye lids. A n t i p s y c h o t i c m e d i c a t i o n c o n s i de de r a b l y i n c r e a s e s t h e c h a n c e o f d e v e l o p i n g angle closure glaucoma. Some drugs which are used to treat schizophrenia a r e k n o w n t o c a u s e p i g m e n t a r y r e t i n o p a t h y .
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Steroids Steroids are generally divided into two types: anabolic and corticosteroids. A s i t w a s p r e v i o u s l y d i s c u ss e d , c o r t i c o s t e r o i d s a r e u s e d t o r e d u c e inflammation in the body. They may also be used to treat breathing disorders such as the asthma (see Asthma Medication). Anabolic steroids, on the other hand, are synthetic steroids that are believed to boost a body’s ability to produce muscles. Steroids are commonly used by
athletes and body builders. Some of the adverse effects caused by steroids are as follows:
Some steroids, such as Glucocorticoids, are photosensitizing. They increase a person’s sensitivity to the sun and undertake a
p h o t o c h e m i c a l r e a c t i o n t h a t w o u l d m o d i f y t h e t i s s u e – m a k i n g a p e r s o n m o r e v u l n e r a b l e t o c a t a r a c t s a n d m a c u l a r d e g e n e r a t i o n.
Steroids can contribute to the development of cataracts, glaucoma, and lead to macular degeneration.
Prolonged use of steroids can cause the intraocular pressure to increase by as much as 50 percent. Cataracts formed by steroids are extremely dense and cause loss of vision extremely quickly.
T h e i n c r e a s e d i n t r a o c u l a r p r e s s ur ur e p a v e s w a y f o r g l a u c o m a . T h e damage done by the increased pressure will remain even if a per son quits using steroids; however, the pressure itself will drop down to normal levels.
Another major problem with use of steroids is the fact that the y increase the blood sugar levels and can thereby lead to diabete s. We have already discussed how diabetes can contribute to numerous eye problems.
Prednisone is a type of steroid that is very damaging to the eye. They
c a u s e d a m a g e t h e o p t i c n e r v e – a n d i n s e v e r e c a s e s , d a m a g e i t t o a n extent that would simply sever the link between the brain and the eyes.
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Vitamins Very high dosage of Vitamin A can lead to increased pressure of the fluid around the brain, leading to swelling of the optic nerve, severe headaches and distorted vision.
Weight Loss Appetite suppressants are usually consumed by people trying to l ose weight. T h e s e s u p p r e s s a n t s c a n l e a d t o d i l a t e d p u p i l s , i n d u c e d i f f i c u l ty i n f o c u s i n g on objects as well as leading to visual problems when reading. Dry eye syndrome can also be caused by them and in severe cases, optic nerve damage and/or glaucoma may follow.
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Section 2 Treating Defective Defecti ve Vision
Chapter 6: Wearing Glasses: Is it safe? Chapter 7: Laser Eye Surgery
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Chapter 6: Wearing Glasses: Is it safe?
The purpose of this book is to help y ou understand the things that affect y o u r e y e a n d , i n t u r n , y o u r v i s i o n . E y e g l a s s e s a r e u n a r g u a bl bl y t h e m o s t common method used by people to correct their vision. Glasses h elp people in viewing objects as they normally would, regardless of whether they are myopic or hyperopic. Vision problems associated with other eye d isorders can also be corrected by use of eye glasses. What a lot of people do not realize is that glasses offer only a temporary solution to their vision problems. In actuality, glasses are found to have deteriorating effects on a person’s eyes. Do you find this hard to believe?
How many people have you encountered whose eye sight just conti nues to deteriorate, requiring them to get a new prescription for their glasses? A l m o s t a l l o f t h e m , r i g h t ? G l a s s e s a c t u a ll y w o r s e n t h e v i s i o n o f a p e r s o n . T h e r e a r e n u m e r o u s r e a s o n s a n d s u p p o r t i n g e v i de n c e f o r t h i s s t a t e m e n t . I n this chapter, we will discuss how and why glasses deteriorate vision problems.
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The Optics of Eye Glasses O n e o f t h e m o s t f u n d a m e n t a l c o n c e p t s o f v i s i o n i s t h a t i t i s n o t s t a t i c – i t changes, constantly. This can be felt by a number of people, especially after a long tiring day of performing tasks that may have required great levels of concentration or perhaps after spending several hours in front of a computer screen. This is when the eyes are tired and it becomes difficult to focus as well as a person usually can. Now the whole purpose of glasses is to correct the refractive error. Most of the vision problems that occur due to refractive error cause the eye’s lens to
incorrectly focus the incoming light. If the light is focused in front of the retina, then myopia is said to occur. On the other hand, if the light is focused behind the retina, this implies hyperopia and a person will have problems in focusing onto closer objects as compared to those t hat are farther off. The way glasses are designed to compensate for this refractive error is, to say the least, not so versatile. Whenever these glasses are worn, the refractive error must remain the same in order for them to work at their peak efficiency. However, it was learned that a person’s vision is not static; rather, it changes even during the day. A person will have bett er vision after a good night’s sleep, as compared to when he or she is about to retire to
bed. These changes in the vision will occur continuously; however, the corrective glasses will not be able to adapt to the changing refractive error. So in essence, even while wearing the glasses, you will experience some kind of vision problems. This situation is further deteriorated if your prescription was for 100 percent correction at the particular time of measurement. The e yes will constantly try to adapt to the conditions that were prevalent at the time of measurement. So rather than the glasses adjusting to your eyes, your eyes will begin and try to adjust to the glasses.
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So if you had your eyes tested af ter work, your eyes would have been quite tired. Nonetheless, your glasses would have been created based on the m e a s u r e m e n t s a t t h a t s p e c i f i c t i m e – s o y o u w i l l s i m p l y b e f o r c i n g y o u r e y e s t o b e c o m e e x a c t l y t h e w a y t h e y w e r e a t t h a t t i m e – t i r e d . If this continues, what do you think will happen to your eyes? They will try to adapt to the glasses, but the slight changes that occur on a daily basis in the vision will be in conflict. Simply put, the eyes will be fo rced to deteriorate in an attempt to get the glasses ‘working right’.
Minus Lenses for Reading People who are myopic are usually prescribed concave or minus l enses to help them see far-off objects. I t has been proven that use of minus lenses can actually deteriorate the vision. Myopic eyes (nearsighted) have to adjust around 3 diopter lenses in order to read corre ctly from a normal reading distance. Diopter is a measure of the power of a lens. That being said, if a person wears a minus three ( -3) diopter lenses in order to correct their distant vision, and begin reading with the same glasses, then their eyes will have to adjust to the value of +3 (positive) diopters as well as t h e – 3 ( n e g a t i v e ) d i o p t e r s . T h i s m e a n s t h a t t h e e y e s w i l l b e r e q u i r e d t o accommodate around 6 diopters for the duration the glasses are used to read. This is precisely what makes distant vision glasses harmful if they are used for reading. Great amount of strain is put onto the eyes w hich in turn can l e a d t o d i m i ni ni s h e d e y e s i g h t . Glasses for near sight are prescribed in order to provide lucid vision from a distance of 6 meters to infinity. Due to the fact that these classes are static and do not adapt to changing circumstances, they will be out of alignment by over 20 times if they are used for reading from a distance of 30 cm (100cm in 1 meter). If a person tries to focus on an object that is 3 meters away, the glasses will help only partly (around 50 percent of the time).
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At this point in time, no glasses have been constructed which c an adapt to c h a n g i n g s i t u a t i o n s ; f o r e x a m p l e , t r a n s i t i o ni n g f r o m r e a d i n g t o l o o k i n g a t distance objects. A video camera, on the other hand, is capable of doing this my moving the lens back and forth to properly focus on the relevant object.
Importance of the Optic Center of Eye Glasses There is located a point in all lenses of eye glasses that provides the best p o s s i b l e v i s i o n. n. T h e y a r e c o n s t r u c t e d i n a w a y w h i c h a s s u m e s t h a t y o u a r e always looking directly ahead of your eyes; whenever you look away from this region, the lens tends to become more of a prism. This point is called t h e o p t i c c e n t e r . You may have observed the prism effect on pictures that are captured through wide-angle lenses. It is edges of these images that are become d i s t o r t e d – a n d t h i s i s p r e c i s e l y w h a t h a p p e n s w h e n a p e r s o n t r i e s t o f o c u s on objects through any area outside that of the optic center. The distortion of images, and in some case, the frame of the glasses itself forces people to use the optic center for viewing purposes. Another common practice to discourage the eyes from ‘wandering away’ from this point is by
installing stronger lenses. However, this technique causes the vision to deteriorate. The optic center plays an important role when the lenses are be ing used for reading. The glasses in this case are designed to be used with the intent of correcting the distance vision problems, so whenever a person looks at distance objects, they do so through the optic center. On the other hand, when a person uses the same spectacles for reading purposes, the eyes tend to frequently ‘exit’ the region of the optic center as you read along the
lines. Except when reading glasses have been prescribed to you for reading, the optic center would generally be more spaced out that it is supposed to b e . T h i s b r i n g s a b o u t a d d i t i o n a l s t r a i n o n t h e e y e s a n d e v e n t u a l ly ly c o n t r i b u t e s s i g n i f i c a n tl tl y t o d a m a g i n g t h e e y e s .
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Another example of the damaging effects of glasses which can be mentioned includes the use of near sight glasses while working on a compu ter. The glasses will not be adjusted properly for the computer screen that would be at a distance of no more than 60 cm from the eyes. This will also alter the way a computer screen affects the vision of a person.
Glasses and Their Effects on the Size of Eyes Plenty of scientific evidence has been gathered that indicates that young primates’ development of eyes was affected when lenses were fitted to
them. Biologists at the New York University have found through extens ive research t h a t u s e o f a m i n u s l e n s ( - ) c a u s e s s i g n i f i c a n t e l o ng n g a t i o n o f t h e e y e b a l l – i n other words, the near sight is deteriorated over time. Similar were the results of using plus lenses (+).
Glasses: Annoyances and Inconvenience Glasses are nothing more than a compromise. They offer only a temporary s o l u t i o n – a s o l u t i o n t h a t a c t u a l l y w o r s e n s t h e e y e s i g h t a s l o n g a s t h e glasses are worn. Not only that, they also offer quite a few an noyances. Even the simplest problem of them fogging up (caused by humidity changes) when you go from one point to another; or the fact that they can be scratched, get dirty or even break can be frustrating! As we proceed further with the book, we will start discussing ways that will h e l p y o u t o h e a l y o u r e y e s n a t u r a l l y , a n d p e r m a n e n t l y .
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Chapter 7: Laser Eye Surgery Tremendous advancements have taken place in the methods used to perform a laser eye surgery. Traditional methods involved use of a scalpel to cut the tissues in the eyes, and this method carried the risk of infections spreading. The onset of laser surgery techniques brought about safer and more efficient surgical procedures to correct vision problems. Laser eye surgery is also known as vision correction surgery o r e v e n r e f r a c t i v e s u r g e r y d u e t o t h e f a c t t h a t t h e y c o r r e c t r e f r a c t i v e e r r o r s . The majority of the laser eye surgery work by altering the shape of the cornea in order to e nsure that the light which enters the eye is focused correctly onto the retina. While other types of surgery go a st e p ahead and replace the natural lens of the eye with a synthetic one. It is also important to understand that not everyone can underg o an eye surgery. The following surgeries require that a person’s eyes be healthy and f r e e f r o m a n y e y e d i s o r d e r s s u c h a s r e t i n a l d i s e a se se s , c o r n e a l s c a r s a n d o t h e r s . T h i s l e a v e s p e o p l e w i t h t h e s e d i s e a s e s v e r y f e w o p t i o n s – o n e o f which is the natural techniques to heal eyes. In this chapter, we will begin by discussing the types of laser surgery available and then we will proceed to talk about the risks that come with them.
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Types of Laser Eye Surgery Several types of surgery are available and they are as follows:
LASIK LASIK is short for laser in-situ keratomileusis. This technique is used to correct vision in people who are either myopic (nearsighted), hyperopic (farsighted) or have an eye condition called astigmatism. LASIK surgery is carried out in order to reshape the cornea to ensure that it can correctly focus incoming light onto the retina. Compared to other surgical techniques, a ‘flap’ is created into the outer layer of the cornea so
that the underlying corneal tissue can be reached. A computer imaging technology called wavefront technology can be used a l o n g w i t h L A S I K t o g e n e r a t e a c o m p r e h e n s iv iv e i m a g e o f t h e c o r n e a .
PRK PRK is short for photorefractive keratectomy. This method of laser surgery is utilized to treat mild-to-moderate myopia, hyperopia and astigmatism. A laser is used to reshape cornea during the procedure. The laser that is used t o p e r f o r m t h e s u r g e r y i s a c o o l p u l s a t i ng ng b e a m o f U V l i g h t . U n l i k e t h e L A S I K eye surgery, this laser is only used on the surface of the cornea and no ‘flap’ is needed to be created in the outer layers.
LASEK L A S E K i s s h o r t f o r l a s e r e p i t h e l i al al k e r a t o m i l e u s i s . I t i s a c t u a l l y a modification of the PRK surgery. A flap (epithelial) is needed to be created f o l l o w e d b y l o o s e n i n g t h e e p i t h e l i a l c e l l s t h e m s e l v e s b y a n a l c o h o l s o l v e n t. Once this has been done, a laser is used to begin the process of reshaping the cornea. The flap is then allowed to heal by securing it wit h a soft contact lens. LASEK surgery can be used to treat astigmatism, myopia, and hyperopia.
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RLE RLE is short for refractive lens exchange, also referred to as clear lens extraction. As its name implies, it’s a procedure carried out to replace the
natural lens of the eye. A small incision is made through which the le ns is extracted and replaced with synthetic lens (plastic or silicone). RLE offers a w a y t o t r e a t s e v e r e f a r s i g h t e d ne ne s s o r n e a r s i g h t e d n e s s i n a p e r s o n .
EpiLasik The EpiLasik surgery procedure is quite similar to PRK in the sense that it requires removal of a very thin layer of the cornea before reshaping it. It is up to the surgeon to re place the thin layer or leave it as it is. Ag ain, the area is secured using a soft contact lens to allow healing.
PRELEX PRELEX is short for presbyopic lens exchange. This procedure allows i m p l a n t a t i o n o f a m u l t i f o c a l l e n s t o c o r r e c t a n e y e d i s o r d e r c a l l e d p r e s b y o p i a ( f o r m o r e i n f o r m a t i o n , s e e t h e c h a p t e r o n E y e C o n d i t io io n s ) .
Intacs Intacs is also known as ICR, or intracorneal ring segments. A small incision is made in the cornea and two crescent -shaped rings made of plastic are placed on the outer edges of the cornea. The purpose of these rings is to ‘flatten’ the cornea, and thereby alter the way the light is focused onto the retina in the eye. Mild myopia can be treated using this procedure; however, other laser procedures are now increasingly being used. On the other hand, keratoconus is the most common eye disorder that is treated by this method.
Phakic Intraocular Lens Implants The phakic intraocular lens implants are specifically designed for those people who have nearsightedness to an e xtent that is untreatable by e ither PRK or LASIK. Such an implant is inserted by created a small incision at the cornea’s edge. The implant is then attached to the iris. The only major
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difference between this procedure and that of the RLE is that t he natural l e n s o f t h e e y e i s l e f t i n t a c t – r a t h e r t h a n r e m o v e d a s i n R L E .
AK AK is s hort for astigmatic keratotomy. This isn’t exactly a laser eye surgery procedure; rather, it is a surgical procedure specifically carried out to c o r r e c t a s t i g m a t i s m . T h e s h a p e o f t h e c o r n e a i s a l t e r e d b y a s t i g m a t i sm s m – t h i s procedure attempts to correct it by making a single or double incisions on the parts of the cornea considered to be the steepest. These incisions cause the cornea to relax and begin to return to its original, rounded shape.
RK RK is short for radial keratotomy. Some time before the advent of more advanced laser surgery procedures, this was among the most commonly used procedures to correct myopia. RK has now been rendered into an obsolete p r o c e d u r e a n d i s r a r e l y u t i l i z e d – e s p e c i a l l y e v e r s i n c e t h e L A S I K a n d P R K were introduced.
Side Effects of Laser Surgery Laser eye surgeries have offered a promising way of getting rid of the most c o m m o n e y e d i s o r d e r s a n d v i s i o n p r o b l e m s . H o w e v e r , t h e s e a d v a n t a ge ge s d o c o m e a t a r i s k . H e r e a r e s o m e t h i n g s t h a t n e e d t o b e t h o r o u g h ly ly c o n s i d e r e d before opting for a laser surgery procedure:
Infections and Delays in Healing T h e r e a r e c o n s i d e r a bl bl y f e w e r c h a n c e s o f d e v e l o p i n g a n i n f e c t i o n a f t e r a n e y e surgery, as compared to the traditional methods of using a scalpel; however, it is not unheard of. Infections following PRK occur in a very small number of people. This number is even smaller for those who have undergon e LASIK surgery. N e v e r t h e l e s s , i f a n i n f e c t i o n d o e s r e s u l t d u e t o t h e e y e s u r g e r y , a d d i t i o n al discomfort along with increased requirement of healing time sho uld be expected.
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Under or Over Correction The chances of success of an eye surgery cannot be precisely predicted, at least not until the eye has fully healed. It may be r equired of patients to continue wearing their eye glasses or contact lenses even after the procedure has been completed. Any under corrections in the surgical procedure can be followed up by yet another procedure, termed a laser enhancement.
Worsening of Vision In most of the cases, the vision of a person improves and he or she may not need to use any contact lenses or eye glasses anymore. Nevertheless, there are also instances where the already bad vision is turned worse. Generally, this is a result of removal of irregular tissue or perhaps due to excessive corneal haze.
Excessive Corneal Haze Corneal haze is a par t of the natural healing process of the eye, following a surgical procedure. In most cases, it has no adverse effect in the long term on a person’s vision. There are instances, however, where this corneal haze
begins to distort the vision. A second surgery may be needed to correct corneal haze problems in such cases.
Regression In several cases, the improvements in a person’s vision following an eye
surgery begin to diminish over time. When this happens, an eye specialist may recommend to the person that he or she undergo a second eye surgery to revive the vision and achieve the best possible results. This makes it clear that even a surgery sometimes cannot heal the vision permanently. There is no alternate to natural healing.
Halos An optical effect called the halo effect sometimes occurs following an eye s u r g e r y , e s p e c i a l l y i n l o w l i g h t c o n d i ti ti o n s . T h i s e f f e c t c a u s e s t h e u n t r e a t e d
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areas of the cornea to produce a second image. This tends to become problematic especially at night, and can severely affect a person’s ability to safely drive at night.
Damage or Loss of Flap As we already know, the LASIK surgery procedure requires a flap to be c r e a t e d o n t h e s i d e o f t h e c o r n e a . T h i s f l a p m a y r e q u ir ir e r e p o s i t i o n i n g a f t e r the surgery; this repositioning may need to be carried out with in the initial few days, or perhaps even a few weeks.
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Section 3 Natural Ways to Improve Eyesight
Chapter 8: Bates’ Method of Improving Eyesight Chapter 9: Importance of a Healthy Diet Chapter 10: Exercises for Improving Vision
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Chapter 8: Bates ’ Method of Improving Eyesight Dr William Horatio Bates was born in Newark, New Jersey in the year 1860. He e arned his medical degree in 1885 and began his exceptional career by working in numerous hospitals around New York City, as well as by practicing privately. H e w a s a l e c t u r e r o f o p h t h a l m o l og y a t t h e N e w Y o r k Postgraduate Hospital and Medical School for 5 years. It was during this time that he also served as an advisor to New York State’s school boards.
Before the onset of the 20
th
c e n t u r y , D r W i l l i a m B a t e s
h a d g r o w n t o b e c o m e q u i t e d i s c o n t e n t ed w i t h t h e p r e v a i l i n g o p h t h a l m o l og og i c a l p r a c t i c e s ; t h i s i s w h a t led him to began his extensive research into the numerous disor ders of the eye and how such things affected the eye sight of a person. It is precisely this research which led to the formation of The Bates Method. T h e c a u s e o f h i s q u e s t i o n i n g t h e c o n v e n t i o n a l m e t h o d s o f o p h t h a lm lm o l o g y began when he noticed that some of his patients who had refractive errors in their eyes had begun to have an improved eye sight, in some cases, the changes were to such an extent that all the symptoms of shortsightedness or farsightedness totally reversed. I t w a s d u e t o t h i s t h a t h e b e g a n q u e s t i o n i n g t h e m o s t b a s i c a s s u m p ti o n s o f the accepted ophthalmological practices. It was, and still is, commonly believed that a person with refractive errors could only be prescribed eye glasses to resolve the symptoms.
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A new set of theories regarding eye sight were created by Dr William Bates based on which he developed a unique method that could help peo ple improve their eye sight and overcome their vision-related probl ems. Over a century has passed since Dr William H. Bates developed his theories about eye sight and formulated a method to heal the eyes; nonetheless, his theories are taught worldwide, with an increasing number of eye specialists a n d p r o f e s s i o n a l s t u r ni ni n g t o t h e B a t e s ’ m e t h o d i n o r d e r t o h e a l t h e i r o w n
patients. His method has been attempted on people with myopia, hyperopia, astigmatism, lazy eye along with more severe diseases such as macular degeneration with exceptional results. This chapter will discuss what Bates’ method is, and how it can be used to
improve eye sight in natural ways without relying on glasses or contact lenses, which are nothing but a temporary aid.
The Bates Method The Bates Method is a simple way of naturally improving eye sight. Due to the fact that it is a natural way and causes no harm to a person, it has become quite popular among many eye care p r o f e s s i o n a l s. s . I t i s c o n t i n ui ui n g t o b e r e c o g n i z e d and respected even after years of never ending d e b a t e s a n d c o n t r o v e r s i es es . However, there are scientists that still are unable to grasp the unique theories of vision which were presented by Dr William H. Bates. The fundamental theories drafted by Dr Bates can be summarized as foll ows:
1. The shape of the eye ball constantly changes as a result of c o n t i n u o u s ly ly s h i f t i n g c o n d i t i o n s o f t h e e y e .
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2. The focus of the eye is also regarded as being in a continuous flux, and this is due to the fact that the eye is looking at both close and distan t objects simultaneously in almost all situations. D e s p i t e b e i n g i n a s t a t e o f c o n s t a n t f l u x, x, t h e h u m a n e y e c a n p r o v i d e v i s i o n b e c a u s e o f i t s a b i l i t y t o c o n t i n u o u s l y a d a p t – t h e e y e ’ s a b i l i t y t o a d a p t i s c a l l e d e y e a c c o m m o d a t io io n . Nevertheless, problems arise when the eye’s ability to adjust (eye accommodation) begins to deteriorate. This deterioration can be due to a number of factors, some of which are as follows:
Weakening of the eye muscles
Poor lighting conditions
Damaged macula
That been said, eye is just like other organs of the body, and are prone to disease and disorders of all kinds. Nevertheless, when the e ye’s ability to
adapt reduces, this causes blurred vision. It is a scientific fact that is accepted by all that distorted vision (blurriness) is caused when the light entering the eye is improperly focused and does not reach the point in retina where it is supposed to reach. If it is focused at the front of retina, myopia is said to occur. When it is focused be hind the re tina, hyperopia is said to occur. Therefore, for perfect vision, the light must be focused precisely onto the retina.
Conventional Way of Treating Vision The conventional way of treating vision involves prescribing ey e glasses to correct the eye sight. The corrective lenses are prescribed by eye specialists and opticians to serve two main purposes:
1. To help the eye see clearly 2 . T o r e d u c e e y e s t r a i n a s a r e s u l t o f d i s t o r t e d v i s i o n ( b y c o r r e c t i ng i t using lenses)
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This convention idea is based on the fact that it is the lens of the eye that is to be blamed for incorrectly focusing the incoming light onto the retina. This is why corrective lenses in the form of eye glasses or contact lenses are p r e s c r i b e d t o b a s i c a ll ll y f u l f i l l t h e s h o r t c o m i n g s o f t h e e y e ’ s n a t u r a l l e n s .
Bates’ Treatment Method Dr William H Bates had the courage to stand up and go against the c o n v e n t i o n a l b e l i e f s o f o p h t h a l m o l og y . H e q u e s t i o n e d t h e v a l i d i t y o f s u c h a method (of conventional method) by stating that due to the eyes being in a constantly changing state, corrective lenses that are constant simply cannot help in healing the eyes; rather, such correction techniques would only increase the strain on a person’s eyes.
This is because by using corrective lenses which were constant, the eyes would be forced to see through them no matter how varying the conditions are; thereby straining the eyes by forcing them to focus in such situations. Dr William Bates’ theory emphasized on the fact that the value of the
prescribed glasses (or contact lenses) may be suitable in one situation but not in another, considering the changing nature of the eye sight. Also, restricting the eyes and forcing them to use the corrective lenses would deprive their ability of adjusting naturally (eye accommodation), which in turn would lead to a continuous deterioration as long as the corrective lenses are worn. Dr Bates’ treatment method was based on the idea that refractive errors were not due to the fault in the eye’s natural lens, but due to the distorted shape of a person’s eye ball.
For myopia to develop, he believed that the compression of the eye ball caused the lens to become flattened. As for hyperopia, it was t he elongation of the eye ball which causes the lens to become thicker.
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Based on these theoretical ideas, his treatment method believes that eye relaxation is the only natural way of restoring vision without any side
effects.
Circle of Eye Strain A normal, healthy eye ball is almost perfectly round. Dr Willia m Ba tes stated that when a person strains their eyes to see something, their eye ball’s
shape begins to deform. This deformation of the natural shape c auses a reduction in vision, which in turn causes the person to strain the eyes more i n a n a t t e m p t t o c l e a r l y s e e . T h e a d d i t i on on a l s t r a i n f u r t h e r d e g r a d e s v i s i o n and causes a person to enter a vicious, on-going circle of poor vision. I t i s t h e B a t e s M e t h o d w h i c h a i m s a t b r i n g i ng a n e n d t o t h i s c i r c l e . T h e p r o b l e m s t a r t s w h e n o n e r e a l i z e s t h a t t h e y c a n n o t c o n s c i o u s l y c o n t r ol the muscles of their eyes. Humans do not have the ability to te ll their muscles not to change the shape of the eye ball. However, what they can do is control these muscles unconsciously through developing awareness. Here is a comparison between Dr Bates’ theories and method of improving e y e s i g h t a n d t h e c o n v e n t i o n a l o p h t h a lm lm o l o g i c a l t h e o r i e s :
Conventional Methods
Dr William Bates’ Method
There is no denying that deterioration of vision results due to incorrect r e f r a c t i o n. n . T h i s c o u l d b e d u e t o t h e i n c o m i ng ng l i g h t b e i n g f o c u s e d e i t h e r i n f r o n t o f , o r b e h i n d t h e r e t i n a . THEORY: The problem of deteriorated
THEORY: The problem of deteriorated
vision is caused by a distortion of the
vision is caused by the distortion of
natural shape of the eye ball.
the eye’s natural lens.
SOLUTION: Normal vision can be
SOLUTION: Vision can be improved by
restored by relaxing the muscles
using corrective lenses (eye glasses
around the eyes in order to prevent
or contact lenses).
them from altering the shape of the eye balls.
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RECOMMENDATION: Use of corrective
RECOMMENDATION: Wear glasses to
lenses prevents the eye’s natural
get clear vision, if they create
ability to adjust (eye accommodation)
problems and distort vision, get a
to differing conditions. The use of
new prescription.
eye glasses or contact lenses forces the eyes to adjust only to the glasses, no matter what the conditions. According to Bates method, allowing the eye muscles to relax can greatly help in improving the vision of a person to such an extent that corrective lenses may not be required.
Principles of Clear Vision T h e f o l l o w i n g p r i n c i p le s o f c l e a r v i s i o n a r e t h e f o c a l p o i n t o f t h e B a t e s Method:
1. Central Fixation The central fixation technique tells us to try to focus only on a single point at any given time. To demonstrate, get your hands onto any printed reading material, and: 1. Focus only on a single word on the page of your reading ma terial; let the other words become blurry around that word. 2. Next, try to focus onto a single letter of that particular word, and see if you can see it more clearly than other letters of the word. 3. Once you have succeeded at that, proceed to look at the other letters of that word one after the other. 4. When you reach the last letter of that word, focus on the blank which is there between that word and the next. 5. Continue the same steps by beginning to focus on the next word that follows.
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The whole objective of the technique called the central fixation is to help a person in focusing onto a small portion. This is because it is the macula that i s r e s p o n s i b l e f o r v i e w i n g t h e f i n e d e t a i l s o f a n y i m a g e . B y p r a c t i c i ng ng t h i s principle technique, a person can enhance the macula’s ability to focus.
2. Shifting Shifting is a technique in which a person trains the eye to foc us on one object to another repeatedly. The difference between the object s should be that one object be closer to the person, and the other farther away. The cycle should be continued with eyes m oving back and forth between the objects. This technique helps in relieving the tension and redu cing the eye s t r a i n . C o n s t a n t b l i n k i ng ng s h o u l d b e d o n e i n o r d e r t o k e e p t h e e y e c l e a n during this practice.
3. Sunning Sunning is a technique which is used to help the eyes to adapt to va rying intensity of lights, especially brighter ones. This technique is performed by a person closing their eyes and gazing at the sun for few seconds. Then the person looks away towards clouds (or the sky, if there are no clouds) and opens the eyes for a few seconds. The process is repeated with opening and closing the eyes at appropriate moments. Sunning technique is known to increase sharpness of vis ion along with reducing or preventing squinting that can cause eye strain .
4. Relaxation Relaxing the eyes is of a core importance to Bates method of improving vision. A person should see complete blackness when the eyes are closed. If gray or yellowish colors are seen when the eyes are closed, then this indicates that the eye is not relaxed c ompletely. Several exercises will be taught in the last chapter of the book that will assist you in improving your vision using the Bates Method and will go a long way in relieving eye strain.
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Chapter 9: Importance of a Healthy Diet
The role of nutrition and its effects on vision has been the center of attention for quite some time now. Detailed research has been c onducted to f i n d o u t h o w p a r t i c u l ar ar f o o d s a f f e c t t h e e y e , e s p e c i a l l y h o w c e r t a i n m i n e r a l s and vitamins influence eye diseases such as AMD (age-related macular degeneration) and cataracts (clouding of the cornea ). A good, balanced nutrition is vital for not only the well-being of the human body as a whole, but also specifically for the eyes. After all, a healthy human body will have the strength to fight off any ailments that it may be inflicted with. Among one of the most significant examples that portray the importance of g o o d n u t r i t i o n f o r h e a l t h y e y e s i s a n e y e c o n d i t i o n c a l l e d x e r o p h t h a l m i a . This is a condition which is common in developing countries and is known to cause blindness in childhood. This condition results from a lack of Vitamin A intake, which could be prevented by consuming fresh vegetables and protein including meat, fish, cheese, eggs, milk, yoghurt, pulses and grains.
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H o w e v e r , m a n y p e o p l e i n d e v e l o p i n g c o u n t r i es a r e d e p r i v e d o f s u c h f o o d s d u e t o p r e v a i l i ng ng p o v e r t y .
Nutrition for the Eyes N u m e r o u s s t u d i e s h a v e r e v e a l e d t h a t a n t i o x i d a n t v i t a m i ns f o u n d i n n u m e r o u s f o o d s h a v e a n i m p o r t a n t l i n k w i t h t h e h e a l t h o f t h e e y e s . S u c h v i t a m i n s h a ve immense significance in keeping the eyes’ cells and tissues healthy. T h e m o s t i m p o r t a n t o f a l l a n t i o x i d a n t v i t a mi n s i n c l u d e V i t a m i n s A , C a n d E . These vitamins are found in numerous fruits and vegetables and should be part of a person’s daily food intake:
Brussel Sprouts
Dried Apricots
Grapefruit
Green Beans
Green Leafy Vegetables (Spinach, lettuce, kale etc.)
Green Peas
Kiwis
Oranges
Peppers
Carrots (Raw)
Tomatoes
They are also found in abundant quantities in daily products (milk, yoghurt, and butter), eggs, seeds and nuts.
Lutein and Zeaxanthin T h e r e a r e t w o t y p e s o f a n t i o x i d a n t s , k n o w n a s c a r o t e n oi oi d s ( c a l l e d L u t e i n , p r o n o u n c e d L o o - t e e n ) a n d Z e a x a n t h i n ( p r o n o u n c e d z a y - a a - z a - t h i n ) . S t u d i e s
have shown that those people who have generous intakes of these two a n t i o x i d a n t s h a v e a d e c r e a s e d r i s k o f d e v e l o p i ng ng a g e - r e l a t e d m a c u l a r degeneration.
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The antioxidants, Lutein and Ze axanthin, are found in both vegetables and fruits. You should consume the following vegetables and fruits regularly and make them a part of your daily diet routine:
Bilberries
Green, Leafy Vegetables (lettuce, spinach, kale, broccoli)
Mangoes
Yellow Peppers
The following foods are rich in Zeaxanthin:
Broccoli
Spinach
Tangerines
Oranges
Eggs
Lettuce (not iceberg lettuce)
Corn
Figure 11: Carrots are a rich source of Vitamin A
The above listed food and vegetables are also rich in Vitamins A, C, and E to varying degrees.
Important Vitamin and Minerals A balanced diet consists of a concoction of vegetables, fruits, meat and dairy products that are consumed on a day to day basis. If a well-balanced diet is made part of a person’s nutritional intake, then that person will definitely
have the required amount of vitamins and minerals necessary for functioning at optimal levels.
Vitamin A Vitamin A is perhaps the most important vitamin for the eyes. It i s absolutely vital for good, clear vision as it helps in protecting the corn ea of the eye. Vitamin A drops are also used to treat dry eye syndrome.
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Vitamin A has also showed up to be effective in treating certai n types of eye inflammation conditions. It is also know to reduce the risk of age-related macular degeneration, a disease that results in severe deterioration of the vision. If vitamin A is consumed along with Lutein (see above), then vision may be prolonged in those people who are s u f f e r i n g f r o m a n e y e c o n d i t i on on c a l l e d
Figure 12: Leafy vegetables are a great source of numerous vitamins and minerals required for a healthy life
the retinitis pigmentosa.
Fruits and Vegetables Rich in Vitamin
A:
Sweet Potatoes
Carrots
Dark, Leafy Green Vegetables
Squash
Romaine Lettuce
Dried Apricots
Cantaloupe Melons
Sweet Red Peppers
Tuna Fish
Mangoes
Vitamin C Vitamin C is a water soluable vitamin that is an extremely effective a n t i o x i d a n t. t. I t h e l p s i n k e e p i n g t h e e y e s h e a l t h y b y p r o t e c t i n g n u m e r o u s parts of the eye from ge tting damaged by UV light. Antioxidants are those substances that protect cells f rom the damaging effects of oxidation.
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Barbara Gollman, who is an expert on functional foods and phytochemicals is also the co-author of the book called The Phytopia Cookbook: A World of Plant-Centered Cuisine, said: "Vitamin C might help prevent cataracts or delay their develop ment, but s t u d i e s d o n o t c o n f i r m t h i s y e t " , “ Cataracts, a clouding of all or part of the “ C lens of the eye, cause blurred or dimmed vision and unusual sensitivity to l i g h t . ”
Figure 13: Citrus fruits are a great source of Vitamin C
M o s t o f t h e A m e r i c a n p o p u l a t i o n c o n s um um e s t h e m i n i m u m r e q u i r e m e n t o f vitamin C (daily intake) of 75 mg for women, and 90 mg for men. However, certain studies have suggested that as much as 300 mg may be required to protect the eyes from cataracts.
Fruits and Vegetables Rich in Vitamin C:
Broccoli
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Brussels Sprouts
Guava
Kohlrabi
Mango
Papaya
Pineapple
Raspberries
Red Bell Peppers
Strawberries
Vitamin E Vitamin E is a fat-soluble vitamin and a strong antioxidant. It is believed that it may help in preventing development of cataracts as well as age related macular degeneration. Vitamin E is found in abundance our food supply, and is found in high concentrations in vegetable oils.
Fruits and Vegetables Rich in Vitamin E:
Almonds
Cottonseed Oil
Fortified Cereals
Hazelnuts
Papaya
Peanut Butter
Sunflower Oil
Sunflower Seed Kernels
Wheat Germ Oil
Wheat Germ
Zinc Zinc plays a very important role for the healthy development of eyes and in t h e i r m a i n t e n a n c e . Z i n c i s f o u n d i n i n t e n s e c o n c e n t r a t i o ns i n t h e e y e a n d i s vital for retina. The requirement for zinc increases as we age; therefore, it is important that sufficient intake of zinc is ensured.
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Fruits and Vegetables Rich in Zinc:
Almonds
Black-Eyed Peas
Brown Rice
Chicken
Garbanzo Beans
Ground Beef
Milk
Sunflower Seeds
Tofu
Wheat Germ
Beta-Carotene Beta-Carotene helps in night vision and keeps the vision at opt imal levels. Beta-Carotene, after it is consumed, is converted into Vitamin A ( excellent f o r e y e s ) a n d c a n b e o b t a i n e d e a s i l y t h r o u g h a n o r m a l , h e a l th y d i e t . T h i s i s why it is not necessary to have beta-carotene supplements.
F r u i t s a n d V e g e t a b l e s R i c h i n B e t a - C a r ot ot e n e :
Apricots
Beet Greens
Cantaloupe Melon
Carrots
Collard Greens
Kale
Papaya
Red Bell Pepper
Romaine Lettuce
Spinach
Sweet Potatoes
Turnip Greens
Winter Squash
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Chapter 10: Exercises for Improving Vision Healthy eyes are undoubtedly one of the most valued assets any person can have. With so many factors out there that contribute to the deterioration of vision, one cannot be too cautious in the attempt to protect the eyes and the vision. What is more disappointing is the fact that wearing corrective lenses (eye glasses or contact lenses) actually contributes to the deterioration of vision. The Bates Method emphasizes on the importance of relaxing the eyes in order to help in restoring the vision as much as possible. Dr William H. Bates believed that people should do away with their glasses and that they adopt a healthy lifestyle along with abandoning incorrect habits and ways of using the eyes. We have already discussed the importance of essential vitamins and nutrients in the previous chapter. The focus of this chapter is to help you l e a r n a b o u t t h e e x e r c i s e s t h a t h e l p i n e l i m i n a t i ng t h e s a i d i n c o r r e c t h a b i t s and to assist the eyes in restoring vision, naturally. One thing that you should keep in mind is tha t these exercises will take time to show results, and will require patience and consistency from your side, along with determination if you are to see the positive results .
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E x e r c i s e 1 – B r e a t h i n g The way a person breathes is vital to the overall health of the person as well as the h e a l t h o f t h e i r e y e s . C o n t r o l l e d b r e a t h i ng empowers a person to be in command of the body. When a person takes a smooth, deep breath, the lungs begin to expand as the air makes its way into them. The deep breath ensures that maximum oxygen content is transported to the lungs, which then extract it to be used by the body’s cells through the
blood stream. However, there are some people who take very shallow breaths, which is opposite to the way it should be. This exercise will help you practice a correct way of breathing that will help you relax and in turn, will benefit the overall health in the positive sense.
Instructions: 1. You can choose to sit down on the floor, on a chair, or even stand with the knees bent slightly. Choose a position that make s you comfortable, and make sure you are in a quiet room. 2. Shut your eyes, gently. 3. Concentrate on your breathing. Pay special attention to the rhythm of your breathing. 4. Take a deep breath, inhaling through the nose while keeping your shoulders loose and drooped. You should inhale at a steady pace and fill up the lungs as much as you can. 5. Hold the breath for about 5 seconds. 6. Begin exhaling at a slow, steady pace through the mouth by pushing from the bottom of your lungs. You will feel your
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s t o m a c h f l a t t e n , d o n o t s q u e e z e t h e a i r o u t – r a t h e r , p u s h i t o u t from the bottom of the lungs. 7. Wait for a minute or two to allow your lungs to rest, and then proceed to the next step. 8 . W h e n y o u a r e r e a d y , r e p e a t t h e p r o c e s s o f i n h a l i ng t h r o u g h t h e nose and exhaling through the mouth, making sure that you push the air out from the bottom of the lungs, and not by flattening your chest. 9. During this exercise, you should concentrate on the rhythm of y o u r b r e a t h i n g c o n t i n u o u sl sl y . 1 0 . M o v e y o u r b o d y o c c a s i o n a l ly ly i n o r d e r t o p r e v e n t l o c k i n g u p o f the muscles. 11. At the end of the exercise (after approximately 3 minutes of controlled breathing), open your eyes slowly and do not focus on any specific thing. Just let your eyes adjust on their own.
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E x e r c i s e 2 – A f f i r m a t i o n s o f V i s i o n H a v i n g a c o r r e c t , o p t i m i s ti ti c a t t i t u d e i s v i t a l f o r i m p r o v i n g y o u v i s i o n . T h e mind and the eyes have a really close bond, and you can use this to your advantage by training your mind to view perfectly. This is an exercise that has more to do with the mind than the eyes themselves. However, the secondary effect of this exercise will be on the eyes. The following affirmations will help the mind to get in the right form which is necessary for naturally improving your eye sight. These affirmations are divided into three categories: Present, Future and Natural.
Present Affirmations
I see clearly
My eyes are powerful
My eyes are calm
My eyes are strain-free
I am making by eyes free of strain by releasing tension
My facial muscles are relaxed
I am curing my eyes
Future Affirmations
I will enhance my eye sight
I will make vision to become sharper than ever
I will make my eyes to focus more naturally
I will completely get rid of any eye strain
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I will heal my eyes
I will make my vision become sharp
Natural Affirmations
I have crystal clear eye sight
My eye sight is improving naturally
I have the ability to improve my eye sight
My vision is as sharp as it can be
Focusing my eyes is becoming easier
I take good care of my eyes
I have been born with he althy and strong eyes
I love to relax the muscles of my eyes
My eye sight can be improved in natural ways
Taking good care of my eyes is ex tremely important
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E x e r c i s e 3 – P a l m i n g Palming is an extremely effective technique that helps the eyes to relax. You can carry out this exercise wherever and whenever you want to. If done correctly, you will feel as if all the tension is being drained from your body.
Instructions: 1. To begin exercising, sit down on a chair w ith your elbows placed on a desk. You should then cup your palms and place them over your e yes. Make sure you do not press onto the eyes; all that is required is that you place your hand gently. 2. Let your shoulders to relax and let yourself sink into the dark ness . 3. Concentrate on the gentle, warm feeling of your hands on your eyes. You must make your mind believe that you will improve your eye sight in a natural way, without relying on any glasses. 4. You should make yourself feel as if your intuition and psychic awareness abilities are being e nergized. This is important, because the Bates Method requires that you train your mind to have a sembla nce of control. 5. Maintain this posture and state of mind for as long as practically possible.
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E x e r c i s e 4 – F i g u r e E i g h t s The aim of this exercise i s to increase the flexibility of your eye muscles in a natural and relaxed manner.
Instructions: 1. Take two deep breaths slowly and steadily. 2 . Y o u c a n c h o o s e t o s t a n d , o r s i t w i t h y o u r f e e t b e i n g a p p r o x i m a te l y a shoulder-width apart. Keep your hands at your sides. The knees should be allowed to slightly bend. 3. Now imagine as if you have a figure of number 8, lying horizontally approximately 15 feet away from you. 4. Let your eyes w ander along the horizontal figure of 8 without allowing your head to move. Begin this in one direction first, followed by the same in the opposite. 5. Keep breathing at a slow, steady pace while continuing to blink your eyes frequently to keep them fresh and clean. 6. Feel the tension in your jaw, and allow it to escape.
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E x e r c i s e 5 – S c a n n i n g Staring is an unhealthy habit as it tends to freeze the eyes’ natural energy as
well as the muscle, thereby hindering the blood flow. On the ot her hand, the technique of scanning is opposite to that of staring. R e p l a c e t h e h a b i t o f s t a r i n g w i t h t h e s c a n n i n g t e c h n i q u e b y f o l l ow ow i n g t h e s e instructions: 1. Take two deep breaths slowly and steadily. 2. You can choose to stand, sit or freely move around. 3. When you look at any object, do not let your eyes to freeze on to it and focus; rather, let them ‘glide’ over the object as if you we re using your
eyes to paint a work of ar t. 4. Keep the breathing steady. 5. As you let your eyes ‘glide’ from one object to another, do not allow them to fixate on any single object. Continue blinking normally to keep the eyes fresh and clean. 6. Once scanning becomes a habit, you will feel that your eyes gli de effortlessly and without any tension at all.
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