Surgical management of labyrinthine fistula with cholesteatoma.

From 684 cases of ear surgery for cholesteatoma performed by one surgeon, 35 had labyrinthine fistulae (incidence 5.1 per cent). Of these fistulae, 79 per cent involved the lateral semicircular canal only; the other sites involved were the other semicircular canals and the cochlea. The fistula test was positive in 54 per cent of cases overall, but in 80 per cent with an extended site fistula (ESF). Three surgical approaches were employed sequentially--staged combined approach tympanoplasty (CAT), open cavity tympanoplasty and attico-antrotomy. Surgically-induced deafness occurred in 3.3 per cent. All surgical groups showed similar hearing results, except for less conductive deafness in the CAT group. Surgical management is discussed with reference to current theories of the erosive effects of cholesteatoma.