Perilymphatic fistula: a histopathologic study.

Over the last two decades, clinical criteria for perilymphatic fistulae have been defined to the extent that differentiation can be made between such fistulae and other balance-affecting disorders such as Meniere's syndrome. On the assumption that the specimens in the temporal bone bank of the University of Chicago Medical School that had been obtained from patients having vertigo, hearing loss, or both, before those clinical criteria were so defined might have been classified incorrectly, we proposed a retrospective histopathologic study, with prediction of two independent variables: a clinical history and physical findings consistent with the diagnosis of perilymphatic fistula and communication between the vestibule and the middle ear adjacent to or via the fissula ante fenestram. Eleven pairs of temporal bones with the histologic diagnosis of idiopathic labyrinthine hydrops were evaluated before the clinical histories relevant to those specimens were reviewed. In one specimen, a communication between the vestibule and the middle ear space was identified. In none of the other specimens was there a similar communication. As this study continued, significance was given to the histologic details of the communication between the middle ear and posterior canal ampulla. The temporal bones without these communications did not have clinical histories consistent with the diagnosis of perilymphatic fistula.