We describe herein our hospital’s treatment policy for patients with otitis media cholesteatoma associated with a semicircular canal fistula and report the test results for semicircular canal fistula sites, fistula depths, postoperative bone conduction, and hearing.
All the patients had a semicircular canal fistula associated with otitis media cholesteatoma and underwent surgery between August 2010 and April 2016 at the Department of Otorhinolaryngology of Kansai Electric Hospital. The semicircular canal fistula depths were classified according to the Dornhoffer and Milewski classification as I, IIa, IIb, and III, and 17 ears with a depth classification of IIa or higher were investigated. Eleven ears were newly operated on, and the other 6 underwent re-operations. All the re-operated ears had been previously operated on at other hospitals. In principle, a canal wall up tympanoplasty was used as the operative method, in view of the importance of the patients’ postoperative quality of life. In all the cases, fistula treatment was conducted in a one-stage operation as the final step of the operation, and the fistula was covered with a piece of thinly sliced cartilage.
The fistula sites were the external semicircular canal in 15 ears and the external semicircular canal plus the anterior semicircular canal and external semicircular canal plus the posterior semicircular canal in 1 ear each. The fistula depths were IIa, IIb and III in 11, 2 and 4 ears, respectively.
Decreased postoperative bone conduction was observed in 5 (29.4%) of the 17 ears that were examined; the decrease in bone conduction in these 5 ears was within the range of 15 dB. Hearing was improved in 9 (56.3%) of the 16 evaluable ears; 1 ear was not evaluable. Postoperative dry eardrums were confirmed in all 17 ears.
Severe postoperative reductions in bone conduction can be prevented by careful and appropriate fistula treatment.
