RESUMO
OBJECTIVE/HYPOTHESIS: Evaluate the treatment of labyrinthine fistula in a large series of middle ear cholesteatomas. STUDY DESIGN: Case series in a tertiary referral center. METHODS: Between January 2001 and December 2007, 361 ears affected by mastoid and middle ear cholesteatoma were operated at our institution. The incidence of labyrinthine fistula, preoperative and postoperative hearing function, preoperative symptoms, type of surgery, and intraoperative findings were all analyzed. RESULTS: The incidence of labyrinthine fistula was 12.7 percent. During surgery the matrix over the fistula was removed in all but one case. A labyrinthine fistula occurred in larger cholesteatomas as demonstrated by the higher number of cases with more than two sites involved (P < 0.001), facial nerve exposed (P < 0.001), and stapes superstructure eroded (P = 0.010). Postoperative change of bone conduction threshold and postoperative dead ears were not significantly different between fistula and nonfistula cases. CONCLUSIONS: The preservation of the bone conduction threshold is a common finding in small fistulas and can be obtained also in "large" fistulas when appropriate surgical technique is used. In fistulas involving the promontory the matrix should be left in situ when the endosteum is involved.