15 cases of labyrinthine fistula operated by one junior staff from November, 1991 to November, 1993 were discussed. 14 cases were caused by cholesteatoma, and one case was caused by an iatrogenic surgical injury during otoneurologic
procedure(petrosal
approach). Clinical symptoms were mainly that of complication i.e. serous or suppurative labyrinthitis, facial palsy, brain abscess, meningitis, mastoid fistula and subperiosteal abscess. Temporal bone CT scan showed 100% sensitivity in detecting
the
lateral semicircular canal erosion, but fistula test proved less useful due to labyrinthine symptoms and high false nagative rate. Postoperative hearing results were more related to the method of fistula repair rather than the size of fistula,
presence
of perilymph leakage or inadverent perilymph aspiration during matrix removal.
A canal plugging procedure, which was helpful in preservation of cochlea function in some cases, may prevent permanent intralabyrinthine fistula formation, and we suggest it as a method in treatment of selected cases of labyrinthine fistula.
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