Labyrinthine Fistula in Chronic Otitis Media Surgery: Management and Outcomes

The objective of this retrospective study was to present the experience on the management of labyrinthine fistula secondary to chronic otitis media in a tertiary center. 263 patients, who underwent tympanomastoidecomy, in Centro Hospitalar Universitario do Porto, between 2015 and 2020 were reviewed, to select only those with labyrinthine fistulas. 26 patients (9.89%) had cholesteatoma complicated by fistula of the lateral semicircular canal. Most frequent symptoms were unspecific, such as otorrhea, hearing loss and dizziness. Preoperative high-resolution computed tomography predicted fistula in 54%. Using the Dornhoffer and Milewski classification, 10 cases (38.46%) were identified as stage I, 15 (57.69%) at stage II, and 1 (3.85%) as stage III. The choice between open or closed surgical procedure was independent of the type of fistulae. The cholesteatoma matrix was completely removed from the fistula and immediately covered by autogenous material. In one patient matrix was left over the fistula. After surgery, hearing (bone conduction) was preserved or improved in 73% of the patients. There was no statistically significant relationship between the extent of the labyrinthine fistula, type of material used in fistula repair and the hearing outcome. Also, we didn't find a statistically significant relationship between extent of the labyrinthine fistula and the presence of facial nerve canal dehiscence, tegmen timpani erosion, sigmoid sinus exposure or ossicular bone erosions. In conclusion, a complete and nontraumatic removal of cholesteatoma matrix over the fistula in a single-staged procedure, is a safe and effective procedure, which achieves a hearing preservation or improvement in most cases.