Clinical presentation and management of labyrinthine fistula caused by chronic otitis media

To describe the clinical presentation and surgical management of patients with chronic otitis media complicated by labyrinthine fistula and to determine clinical indicators that predict postoperative hearing outcome, I performed a retrospective analysis at an academic tertiary care center. Thirty-four patients with labyrinthine fistula as a complication of chronic otitis media, documented at mastoidectomy, underwent postoperative audiometry. The median age was 50 years, and the duration of otologic symptoms ranged from 2 months to more than 40 years. On presentation, 3 patients had anacusis in the affected ear, while in the others, the pure tone average for bone conduction at the 0.5-, 1-, 2-, and 4-kHz frequencies was 34 dB hearing level. Nineteen patients (56%) complained of dizziness on presentation. The fistula test was positive in 14 of 28 patients (50%). The fistula was detected radiologically in 10 of 24 patients (42%). Cholesteatoma was present in 33 of 34 patients (97%). The lateral semicircular canal was the most common site of labyrinthine fistula. The cholesteatoma matrix was completely removed in 29 of 33 cases and exteriorized in the remaining 4. Of the 31 patients with measurable hearing preoperatively, anacusis occurred in 8 (26%). In 6 of these, the preoperative pure tone average for bone conduction was greater than 50 dB hearing level, and cholesteatoma matrix and granulation tissue invading the membranous labyrinth were found at surgery. I concluded that in chronic otitis media, labyrinthine fistulas occurred almost exclusively in the presence of a cholesteatoma. Postoperative hearing outcome correlated with the size of the fistula and the presence of granulation tissue invading the labyrinth, which could be predicted by the preoperative audiometry.