Table 1. What passes through the major foramina, fissures, and canals of the canine skull. Organized according to physical proximity on the skull. a=artery; aa=arteries; CN=cranial nerve; n=nerve; nn=nerves; v=vein; vv=veins. F or or am am i na na , Fi Fi s su su r e, e, o r C an an al al Externally viewable Mental foramina Mandibular fo foramen Mand Mandiibula bularr canal anal
Palatine fissure
Major palatine foramen Mino Minorr pal palat atin ine e for foram a miina Caudal pa palatine fo foramen Sphenopalatine foramen Fossa Fossa for for the the lacr lacrima imall sac sac Infraorbital foramen Maxillary foramen Infraorbital canal Optic canal Orbital fissure
Rostral alar foramen Caudal alar foramen Alar canal Oval foramen Musculotubal canal Foramen lacerum Stylomastoid foramen Tymp Tympan anoo-oc occi cipi pita tall fiss fissur ure e
Retr Retroa oart rtic icul ular ar fora forame men n Hypoglossal canal Foramen magnum
Internally Internally viewable Round foramen
Carotid canal Canal Canal for for the trige trigemin minal al nerve nerve Internal acoustic meatus Jugular foramen
Foramen for the dorsal sagittal sinus Transverse canals Condyloid ca canals
T ra ra ns ns m itit t ed ed S t ru ru c tu tu r es es
Mental a, v, n Branches of of th the in inferior al alveolar a, a, v, v, n Ment Mental al / infe inferrior ior alv alveola eolarr a, v, and and n bet between wee n the the mand mandib ibul ular ar for fora am men en and the mental foramina Anastomoses between the palatine, infraorbital and nasal aa and vv Incisive duct to vomeronasal organ Major palatine a, v, n Bran Branc ches hes of of the th e maj major pala palattine ine art arter ery y Major pa palatine a, a, v, v, n Sphenopalatine a, v Caudal nasal n Lacri Lacrimal mal sac, sac, cont continu inued ed as as the the bony bony lacrim lacrimal al cana canal, l, which which hous houses es the the nasolacrimal duct Infraorbital a, v, n Maxillary a, v, n Maxillary / infraorbital a, v, n between the maxillary and infraorbital foramina Optic n (CN II) Internal ophthalmic a Oculomotor n (CN III) Trochlear n (CN IV) Ophthalmic division of trigeminal n (CN Vi) Abducens n (CN VI) External ophthalmic a Orbital venous plexus Maxillary a, v Maxillary division of trigeminal n (CN Vii) Maxillary a, v Maxillary a, v throughout length Maxillary division of trigeminal n (CN Vii) through rostral portion Mandibular division of trigeminal n (CN Viii) Auditory tube A loop of the internal carotid a Facial n (CN VII) Glos Glosso soph phar aryn ynge geal al n (CN (CN IX) IX) Vagus n (CN X) Spinal accessory n (CN XI) Sympathetic nn Internal carotid a Sigmoid venous sinus enters fissure fissure from within the skull. skull. Within the fissure, the sigmoid sinus anastomoses with the ventral petrosal venous sinus. The combined vessel then splits and exits the t.o. fissure as the vertebral and internal jugular vv Temp Tempor oral al veno venous us sinu sinus s (eme (emerg rges es as the the ret retro roar arti ticu cula larr vei vein n and and join joins s the maxillary vein) Hypoglossal n (CN XII) Spinal cord Basilar a Venous plexus Spinal part of spinal accessory n (CN XI) Maxillary division of trigeminal n (CN Vii) en route to alar canal Internal carotid a Trigem Trigemina inall ganglio ganglion n is locate located d in this this canal canal Facial n (CN VII) Vestibulocochlear n (CN VIII) Glossopharyngeal n (CN IX) Vagus n (CN X) Spinal accessory n (CN XI) Sigmoid venous sinus Dorsal sagittal venous sinus Transverse venous sinus Basilar venous sinus (a branch of the sigmoid ve venous sinus)
Portions of this table are adapted from Canine Anatomy , B. J. Smith, 1999, National Veterinary Medical Series (NVMS), Philadelphia: Lippincott, Williams, & Wilkins, 619 pp.
