Vestibular pathophysiologic changes in experimental perilymphatic fistula
Journal
Annals of Otology, Rhinology & Laryngology
Journal Volume
101
Journal Issue
7
Date Issued
1992-01-01
Author(s)
Abstract
An animal model of experimental perilymphatic fistula (EPLF) was developed in the guinea pig in order to study vestibular pathophysiology. In experimental animals, 4 μL of perilymph was suctioned from one cochlea via the round window membrane. Changes in vestibular function were as follows. 1) During the acute stage (5 hours postoperatively), spontaneous nystagmus directed toward the normal side was noted in 57.4% of the EPLF animals. This lasted less than 24 hours. 2) One week postoperatively, direction-fixed positional nystagmus toward the lesioned ear was present in 22.7% of the EPLF animals, especially when the lesioned ear was positioned inferiorly. 3) With the ice water caloric test, no response was present in 58.1% of the EPLF animals and an irregular response was found in 22.6% of them, 1 week postoperatively. These results tend to indicate that tests of vestibular function may differentiate between patients with Meniere’s disease and those with perilymphatic fistula. Histologic findings indicate that a floating labyrinth is the cause of positional nystagmus and caloric irregularity. The absence of caloric responses was associated with collapse of the vestibular labyrinth. © 1992, SAGE Publications. All rights reserved.
Subjects
caloric test | experimental perilymphatic fistula | floating labyrinth | vestibular atelectasis
Type
journal article