Preservation of cochlear function after extensive labyrinthine destruction.

Four ears are presented with extensive destruction of the bony and membranous labyrinth with the loss of caloric function but with retention of hearing. Fourteen similar cases described previously in the literature are reviewed. Our cases are unique in that hearing was preserved after surgical removal of the disease in the inner ear itself. We are unaware of any previous well-documented reports showing such extensive destruction of the pars superior portion of the labyrinth with the preservation of hearing. Possible explanations and theoretical implications are discussed.