ORIGINAL ARTICLE
Repair of Acquired Posterior Choanal Stenosis and Atresia by Temperature-Controlled Radio Frequency With the Aid of an Endoscope Qin ying Wang, MD; Liang Chai, MD; Shen qing Wang, MM; Shui hong Zhou, MD; Yu yu Lu, MM
Objectives: To exa examin minee the cli clinic nical al eff effect ectss of tem temper peraa-
ture-controlled radio frequency (TCRF) repair of acquired qui red cho choana anall ste stenos nosis is and atr atresi esiaa wi with th the aid of an endoscope and to discuss the value of acquired choanal stenosis and atresia typing in clinical therapy. Design: Retrospective study. Setting: Acade Academic mic otorhi otorhinolary nolaryngolo ngologic gic referral center center..
Thirty rty-tw -two o pat patien ients, ts, age aged d 32 to 65 yea years, rs, wit with h Patients: Thi acquired choanal stenosis and atresia (from trauma in 9 cases and from radiotherapy after nasopharyngeal carcinom cin omaa in 23 cas cases) es);; 13 cas cases es wer weree bil bilate ateral ral,, and 19 wer weree unilateral. Tran ansn snas asal al TC TCRF RF re repa pair ir wi with th the ai aid d of Interventions: Tr an end endos osco cope. pe. Acq Acqui uired red cho choana anall ste steno nosis sis and atr atresi esiaa can be di divid vided ed int into o 3 typ types:type es:type 1, di diagn agnose osed d wi withi thin n 3 mo month nthss of the causative trauma or radiotherapy; type 2, diagnosed between 3 and 6 months after the trauma or radiotherapy; and type 3, diagnosed more than 6 months after the trauma or radiotherapy. All patients with types 1 and 2 disease received nasal stents made from Silastic that were fixed with transseptal sutures. However, patients with type 3 disease received no stenting.
scan and the surgical results were also analyzed. There was no significant correlation between them (P ( P Ͼ .05). Results: Twenty-nine patients remained free of symp-
toms for 12 to 42 months after surgery. Three patients requi req uired red rev revis isio ion n su surge rgery, ry, inc inclu ludi ding ng 2 ca case sess of typ typee 1 di dissease (3 sides) and 1 case of type 2 (1 side). Two of the patients who underwent revision recovered completely, with no restenosis at 12 months after the second surgery. However, 1 patient with type 1 bilateral atresia experienced another restenosis and required another revision, through a transpalatal approach. There were no postope pos toperati rative ve com compli plicati cations ons.. Ther Theree was wasno no sig signifi nificant cant correlatio rela tion n bet betwee ween n thic thickne kness ss of the sten stenosi osiss reve reveale aled d by com com-puted tomographic scan and the surgical results. Conclusions: We describe a TCRF technique with the
aid of an endoscope for choanal repair. In our experience, it has been a highly successful, safe, and effective proced pro cedure ure,, wi with th min minima imall blo blood od los loss, s, swi swift ft rec recove overy, ry, and short time of hospitalization. It is important in postoperative care to remove any granulation or polyps at the site of the neochoana. Types 2 and 3 are the best types of disease to treat with this procedure.
Main Outcome Measures: The thickness of the ste-
nosis and atresia revealed by computed tomographic
T Author Affiliations: Department of Otolaryngology, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang, China.
Arch Otolaryngo Otolaryngoll Head Neck Surg. Surg. 2009;135(5):46 2009;135(5):462-466 2-466
HERE ARE CONGENITAL AND
acquired choanal atresias (CAs). Most acquired CAs are fibrous membranous atresias. Many approaches have been used in the repair of CA, including clud ing transn transnasal, asal,transp transpalata alatal, l, and transseptal approaches. The transpalatal approach pro ach off offers ers exc excell ellent ent exp exposu osure re and hig high h success rates. However, increased operative time, bleeding, palatal fistula, palatal muscle dysfunction, and maxillofacial disturbances are possible sequelae of this procedure.1 Technical advances and experience in endoscopic nasal surgery have provided
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the opportunity to use a transnasal endoscopicc appro scopi approach. ach. The transna transnasal sal endoscopic sco picapp approac roach h has hasbee been n succ success essfull fullyy use used d over the past decade in the treatment of CA.2-12 The tec techni hnique que pe permi rmits ts a di direc rectt approach pro ach to the atr atreti eticc are area, a, wi with th the ad advan van-tages of an angled view, good illumination, and magnification of the CA. We descri describe be an endosco endoscopic pic surgic surgical al technique and the clinical types of acquired choanal stenosis and atresia that may dec decrea rease se the rat ratee of res resten tenos osis is in sur sur-geryfor gery foracq acquire uired d cho choanal analsten stenosi osiss and andatre atre-sia. We also discuss the value of acquired choanal stenosis and atresia typing for clinical therapy. WWW.ARCHOTO.C WWW .ARCHOTO.COM OM
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I S
Figure 1. Rigid endoscopic findings. The choana was almost completely closed with just a fissure remaining. I indicates inferior turbinate; S, nasal septum.
METHODS Thirty-two patients withacquired choanal stenosis and atresia were treated with transnasal temperature-controlled radio frequency (TCRF) procedures with the aid of an endoscope between January 2000 and December 2006. There were 21 men and 11 women,aged32 to65 years (mean age, 49.5years), with the conditions arising from trauma in 9 cases and radiotherapy after nasopharyngeal carcinoma in 23 cases. Thirteen cases were bilateral, and 19 were unilateral. All patients were diagnosed by endoscopic examination ( Figure 1) and computed tomographic (CT) scan ( Figure 2). The stenosis and atresia were located in the posterior part of the nasal cavity and the edge of the choana. The thickness of the stenosis and atresia ranged from 0.2 to 3.0 cm. Choanal stenosis and atresiaoccurred 2 to 24 months (mean, 9.3 months) after trauma or radiotherapy. Based on the time of injury of the posterior choana as inferred from the inflammation encountered during surgery, acquired choanal stenosisand atresia can be divided into 3 types: type 1, diagnosed within 3 months of the causative trauma or radiotherapy; type 2, diagnosed between 3 and 6 months after the trauma or radiotherapy; and type 3, diagnosed more than 6 months after the trauma or radiotherapy. Four of our cases were type 1 disease (6 sides), 19 were type 2 (26 sides), and 9 were type 3 (13sides).
SURGICAL TECHNIQUE We conducted the transnasal TCRF procedure with the aid of endoscopy using a System 2000 Atlas Coblator II (ArthroCare Corporation, Austin, Texas); an endoscopic and video system (Stryker Corporation, Kalamazoo, Michigan), which included a 4-mm 0° and 30° telescope; Blakesley forceps; and a power soft-tissue shaver (Linvatec Corporation, Largo, Florida). General anesthesia was used. Additional nasal decongestion was achieved by applying a solution of 1% lidocaine hydrochloride and 0.25% phenylephrine hydrochloride to neurosurgical cotton pledgets that were carefully placed in the nasal cavity. A solution of 1% lidocaine hydrochloride with 1:100 000 epinephrine was administered with a spinal needle to the stenosis, atretic plate, and posterior septum under direct visualization. In patients with bilateral stenosis and atresia, the anesthetic was administered to both sides during the inspection. Under endoscopic visualization, a radiofrequency knife was used to trim the scarred mucosa in the posterior choana. Additional scar tissue on the posterior septum and posterior end
Figure 2. Computed tomographic findings of the face demonstrate a membranelike soft tissue density obliterating the bilateral choana (lower arrow), but no osseous component is identified. The anterior nasal passage is quite patent (upper arrow).
of the inferior or middle turbinate was excised with the power soft-tissue shaver and Blakesley forceps. Partial resection of the posterior edge of the vomer was performed with backwardbiting forceps, which were then also used to reduce a portion of the posterior bony septum, further enlarging the neochoana. Care was taken not to damage normal adjacent nasal mucosa. The nasopharynx was carefully examined to rule out tumor recurrence, and surgical specimens were sent for histologic examination. When the surgi cal procedure was compl ete, a custo mmade soft Silastic (Dow Corning,Midland, Michigan) stent with a foam cuff (Bivona Corporation, Gary, Indiana) was placed in the neochoana and secured with a transseptal 2-0 silk suture. In 4 patients with type 1 disease and 19 patients with type 2, stenting was performed using these Silastic stents. In the 9 patients with type 3 disease, no stent was inserted. Antibiotic and local glucocorticoid (0.05% mometasone furoate aqueous nasal spray; Schering Plough Labo NV, Brussels, Belgium) were administered postoperatively.
POSTOPERATIVE CARE Oral amoxicillin with clavulanic acid was prescribed for 2 weeks to preventinfection.Endoscopic follow-up wasperformedweekly, andblood clots andcrusts were removed or suctioned. After removal of the nasal packs, all patients were trained and advised to perform nasal douches with normal saline (isotonic sodium chloride) solution at least 3 times a day. Mometasone furoate, 0.05%, aqueous nasal spray was also administered twice per day. The patients were seen weekly for the first 2 postoperative weeks to change the nasal packing. They were then observed every 2 weeks for 1 month, monthly for 2 months, and then once per 3 months. Inthe 4 type1 cases,the stent was removed within 2 to 4 weeks (mean, 3 weeks). In the 19 type 2 cases, the stent was
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S
N
T
Figure 3. Endoscopic view of the choanal passage 15 months postoperatively. The choanae were quite patent. N indicates nasopharynx; S, nasal septum; T, torus.
removed within 1 to 2 weeks (mean, 1.5 weeks). In the 9 type 3 cases, no stentwas used.Stents were removed under topical anesthesia, and a meticulous cleaning was performed. The follow-up period was between 12 and 42 months (median, 27 months). At thefollow-upvisits, an endoscopic examination was performed, andany granulationtissue or polyps at the site of the neochoana were removed at that time. RESULTS
Histologic analysis of the resected tissue revealed respiratory stromaltissue lined withepithelial cells and chronic inflammation, edema,andfibrosis butno tumor cells.The overall follow-up period was 12 to 42 months. Twentynine patients (91%) remained free of symptoms, and the diameter of the neochoana was larger than 1 cm after the procedure (Figure 3). However, at 2 months after surgery, restenosis was observed in 3 patients, representing 2 type 1 cases (3sides) and 1 type case (1side). This restenosis was discovered during an endoscopic examination. Two of the patients who required revision recovered completely, with no restenosis at 12 months after the second procedure. However, 1 patient with type 1 bilateral atresia (caused by trauma) experienced another restenosis and required another revision through a transpalatal approach 3 months after a second repair. There were no further postoperative complications (Table 1). The thickness of the stenosis revealed by CT scan and thesurgical results were also analyzed (Table 2). The procedure was considered successful if the patient remained free of symptoms and the diameter of the neochoana was no less than 1 cm at follow-up 12 months after the procedure. COMMENT
Choanal atresia can be either congenital or acquired, although most cases are congenital. Acquired choanal stenosis and atresia are often complications of chemical cauterization, nasopharyngeal carcinoma and radiotherapy, surgical trauma, and infectious disease.13-15 Most ac-
quired cases are fibrous membranous stenoses and atresias. Most arerelated to radiotherapy; in thepresent study, 23 of 32 cases (72%) were the result of radiotherapy. Manysurgical approaches have been suggested for the treatment of choanal stenosis andatresia, including transnasal, transpalatal, transantral, sublabial-transnasal, and transseptal approaches. The transpalatal approach offers excellent exposure and high success rates. However, increased operative time, bleeding, palatal fistula, palatal muscle dysfunction, and maxillofacial disturbancesarepossible sequelae of this procedure.1 The transnasal approach has narrow exposure and limited possibility to develop mucosal flaps. It also has the risk of possible injury to the eustachian tube and skull base.16 Advantages of a TCRF approach with the aid of a rigid endoscope in the repair of choanal stenosis and atresia are clear vision of the operative field and accurate removal of the stenosis and atresia plate without damaging neighboring structures, thus significantly reducing the rate of restenosis. The TCRF approach is a safe procedure with minimal blood loss, swift recovery, anda short time of hospitalization. It is also convenient, in postoperative care, to remove any granulation or polyps at the site of the neochoana at follow-up visits. Congenital and acquired choanal stenoses and atresias differ in structure and in the areas blocked; in addition, the structures in acquired choanal stenosis and atresia can change with development. These differences have clinical value, so we divided acquired choanal stenosis and atresia into 3 types. Type 1 had patent inflammation, abundant secretions, and scar tissue in the nasopharynx and bled freely. The tissue of the nasopharynx and choanae were significantly edematous after surgery. As a result, the restenosis rate in type 1 cases was higher than in types 2 and 3. Two patients with type 1 disease experienced restenosis within 2 months of surgery. The recurrence rate in type 1 cases was 50% (2/4). This was clearly the worst type for the operation. Type 2 is a better type to operate on. Type 2 cases showed a lower restenosis rate; there was1 case of restenosis within 2 months of surgery (recurrence rate, 1 of 19 [5%]). Type 3 cases had almost no inflammation in the nasal cavity and dryer mucosa; there was no case of type 3 restenosis in this study. Thus, type 3 is the optimal type to undergo operation, but the procedure should be performed in patients with type 2 or type 3 disease. The use of stents in the management of patients with CA is a subject of some controversy. Several authors advocate postoperative stenting. Stents are generally left in place for 6 to 8 weeks because this is considered to be the time necessary for the reepithelialization of the neochoana.1 Many materials have been used for stenting, and softer materials apparently give better results in terms of preventing restenosis.17 We believe that stents are useful to stabilize the nasal airwayin the postoperative period and to prevent the development of stenosis by maintaining a lumen. However, stents can also serve as a nidus for infection, and there is a question whether such a foreign body maycontribute to choanal stenosis,as an endotrachealtube may cause subglottic stenosis. We have empirically used readily available Silastic stents for 2 to 4 weeks in type 1 cases and for 1 to 2 weeks in type 2 cases (stenting was not
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Table 1. Transnasal Endoscopic Repair of Choanal Atresia and Choanal Stenosis in 32 Patients Disease Type
Patient
Laterality
Follow-up, mo
Stent Duration, wk
Result
1
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32
Bilateral Unilateral Unilateral Bilateral Unilateral Unilateral Bilateral Unilateral Unilateral Unilateral Bilateral Unilateral Unilateral Bilateral Unilateral Unilateral Bilateral Bilateral Bilateral Unilateral Bilateral Unilateral Unilateral Unilateral Bilateral Bilateral Unilateral Bilateral Unilateral Unilateral Unilateral Bilateral
40.0 42.0 17.5 16.0 23.0 28.0 34.0 31.0 35.0 18.0 21.0 24.0 26.0 29.0 42.0 41.0 38.0 37.0 33.0 13.0 16.5 15.0 12.0 21.0 34.0 42.0 38.0 18.0 25.0 17.0 23.0 12.0
3.5 3.0 2.0 4.0 1.0 1.5 2.0 1.5 2.0 1.5 2.0 1.0 1.0 2.0 1.0 1.5 1.0 2.0 1.0 2.0 1.0 1.5 2.0 0 0 0 0 0 0 0 0 0
Repair Repair Revision Revision Repair Repair Repair Repair Repair Repair Repair Repair Repair Repair Repair Repair Repair Repair Repair Repair Revision Repair Repair Repair Repair Repair Repair Repair Repair Repair Repair Repair
2
3
carried out in our patients with type 3 disease). We usually maintain a regimen of oral antibiotics for our patients for the duration of stenting to lessen the risk of purulent rhinorrhea. Mometasone furoate, 0.05%, aqueous nasal spray was also used to lessen mucosal edema in the nasopharynx. Ourstudy demonstrated that it is possible to find treatments that allow a reductionor even avoidance of the period of postoperative stenting. We followed the technique of mucosal preservation indicated by Andrieu et al18 in their description of the transseptal approach for the repair of CA. The TCRF system and power soft-tissue shavers are believed to be less traumatic to nasal tissue than traditional endoscopic surgical techniques, allowing better tissue healing.19-21 Thus, TCRF and power soft-tissue shavers were used in our study.Some patients whose disease wascaused by trauma showed significant proliferation of fibrosis in choanal stenoses and atresias. The TCRF system is easier and safer to use than power soft-tissue shavers in cases of fibrosis. We think that the TCRF technique helped to reduce the postoperative recurrence rate and the period of postoperative stenting. Furthermore, the shortened period of stenting and the use of soft stents diminished the likelihood of granulation tissue formation and therisk of postoperative infection. On removal of the stent, endoscopic examination of the neochoana was carried out to ensure patency. If necessary, reactionary polyps at or near the neochoana were
Table 2. The Thickness of the Stenosis and/or Atresia and Surgical Results a Thi ckness, cm
Pat ients, No.
Repair s
Revisi ons
12 11 9
11 10 8
1 (Type 1) 1 (Type 2) 1 (Type 1)
0.0-1.0 1.1-2.0 Ͼ2.0
a Unless otherwise indicated, data are reported as number of patients. For the comparison of type 1 with type 2 revisions, 2 =0.048 (P Ͼ .05).
removed. Thecases of restenosis in this study related primarily to granulation tissue or polyps at the site of the neochoana that were not removed owing to the lack of endoscopic examination. Preoperative assessment by means of a CT scan and rigid endoscopic examination is very important for the success of surgicaltreatment. Axial CT scanning andrigid endoscopy can confirm the clinical diagnosis. In fact, CT scans can accurately characterize the nature and thickness of the atresia, the narrowing of the posterior nasal cavity, and the thickening of the vomer.22 In our series, all patients received a preoperative CT scan and rigid endoscopic examination to assess the thickness and nature of the atretic plate, the deformity of the posterolateral aspect of thenasal cavity, andthe presence andnature of anatomic deformities at thelevel of thevomer and pos-
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terior nasal cavity to choose the most suitable surgical approach. However, our study findings suggest no significant correlation between thickness of the stenosis revealed by CT scan and the surgical results. In conclusion, a transnasal TCRF approach with the aid of an endoscope is a useful procedure for the repair of acquired choanal stenosis and atresia. This technique permits an angled vision,excellent visualization, and magnification of the atretic plate; compared with traditional techniques, thistechnique allowed a shorter hospital stay and less blood loss. To reduce the chance of restenosis and shorten or even avoid the period of postoperative stenting, thorough mucosal preservation of the neochoana is of paramount importance. Postoperative care is also important for removing any granulation or polyps at the site of the neochoana. Type 2 and 3 are the best types to consider for the operation. Submitted for Publication: November 23, 2007; final revision received April 14, 2008; accepted May 12, 2008. Correspondence: Qin ying Wang, MD, Department of Otolaryngology, The First Affiliated Hospital, College of Medicine, Zhejiang University, 310003, Hangzhou, Zhejiang, China (
[email protected]). Author Contributions: Drs S. Wang and Lu had full access to all the data in the study and take responsibility for the integrity of the data and the accuracy of the data analysis. Study conceptanddesign: Q. Wang, Chai, S.Wang, andLu. Acquisition of data: Q. Wang, S. Wang, and Zhou. Analysis and interpretation of data: Q. Wang. Drafting of the manuscript: Q. Wang, Chai, S. Wang, Zhou, and Lu. Critical revision of the manuscript for important intellectual content: Q. Wang and S. Wang. Statistical analysis: Q. Wang, Chai, and Zhou. Administrative, technical, and material support: Q. Wang. Studysupervision: S. Wang and Lu. Financial Disclosure: None reported. REFERENCES 1. Brown OE, Pownell P, Manning SC. Choanal atresia: a new anatomic classification and clinical management application. Laryngoscope . 1996;106(1, pt 1): 97-101.
2. Teissier N, Kaguelidou F, Couloigner V, Franc¸ois M, Van Den Abbeele T. Predictive factors for success aftertransnasal endoscopic treatment of choanal atresia. Arch Otolaryngol Head Neck Surg . 2008;134(1):57-61. 3. Pardo Romero G, Mogollo´n Cano-Corte´s T, Pando Pinto JM, et al. Endoscopic treatment for choanal atresia. Acta Otorrinolaringol Esp . 2007;58(1):34-36. 4. James FM, Parente EJ, Palmer JE. Management of bilateral choanal atresia in a foal. J Am Vet Med Assoc . 2006;229(11):1784-1789. 5. Anderhuber W, Stammberger HR.Endoscopic surgery of uniand bilateral choanal atresia. Auris Nasus Larynx . 1997;24(1):13-19. 6. Lazar RH, Younis RT. Transnasal repair of choanal atresia usingtelescopes. Arch Otolaryngol Head Neck Surg . 1995;121(5):517-520. 7. Josephson GD, Vickery CL, Giles WC, Gross CW. Transnasal endoscopic repair of congenital choanalatresia: long-termresults. ArchOtolaryngolHeadNeck Surg . 1998;124(5):537-540. 8. Deutsch E, Kaufman M, Eilon A. Transnasal endoscopic management of choanal atresia. Int J Pediatr Otorhinolaryngol . 1997;40(1):19-26. 9. Uri N, Greenberg E. Endoscopic repair of choanal atresia: practical operative technique. Am J Otolaryngol . 2001;22(5):321-323. 10. WiatrakBJ. Unilateral choanal atresia: initialpresentationand endoscopicrepair. Int J Pediatr Otorhinolaryngol . 1998;46(1-2):27-35. 11. VickeryCL, Gross CW.Advanced drilltechnologyin treatmentof congenital choanal atresia. Otolaryngol Clin North Am . 1997;30(3):457-465. 12. Yaniv E, Hadar T, Shvero J, Stern Y, Raveh E. Endoscopic transnasal repair of choanal atresia. Int J Pediatr Otorhinolaryngol . 2007;71(3):457-462. 13. Ku PK, Tong MC, Tsang SS, van Hasselt A. Acquired posterior choanal stenosis and atresia: management of this unusual complicationafter radiotherapyfor nasopharyngeal carcinoma. Am J Otolaryngol . 2001;22(4):225-229. 14. Bonfils P, de Preobrajenski N, Florent A, Bensimon JL. Choanal stenosis: a rare complication of radiotherapy for nasopharyngeal carcinoma. Cancer Radiother . 2007;11(3):143-145. 15. Miho H, Kato I, IwatakeH, Akao I, Takeyama I. A case reportof acquired choanal atresia. Acta Otolaryngol Suppl . 1996;522:111-115. 16. Morgan DW, Bailey CM. Current management of choanal atresia. Int J Pediatr Otorhinolaryngol . 1990;19(1):1-13. 17. Carpenter RJ, Neel HB III. Correction of congenital choanal atresia in children and adults. Laryngoscope . 1977;87(8):1304-1311. 18. Andrieu J, Guitrancourt P, Stipon M. Chirurgiede l’imperforation choanale . Paris, France: EMC Editions Techniques; 1994. 19. Krouse JH, Christmas DA Jr. Powered instrumentation in functional endoscopic sinus surgery, II: a comparative study. Ear Nose Throat J . 1996;75 (1):42-44. 20. Powell NB, Riley RW, Guilleminault C. Radiofrequency tongue base reduction in sleep-disordered breathing: a pilot study. Otolaryngol Head Neck Surg . 1999; 120(5):656-664. 21. Thiagalingam A, D’Avila A, McPherson C, Malchano Z, Ruskin J, Reddy VY. Impedance and temperature monitoring improve the safety of closed-loop irrigated-tip radiofrequency ablation. J Cardiovasc Electrophysiol . 2007;18 (3):318-325. 22. Brown OE, Smith T, Armstrong E, Grundfast K. The evaluation of choanal atresia by computed tomography. Int J Pediatr Otorhinolaryngol . 1986;12(1): 85-98.
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