Perilymphatic Communication Routes in the Auditory and Vestibular System

Abstract

Horseradish peroxidase was injected into the foramen magnum and oval window of guinea pigs to determine perilymphatic communication routes and boundaries. The primary route to the auditory system appeared to be through the cochlear aqueduct. Perineural spaces of the eighth nerve contributed to this communication and provided the principal perilymphatic communication routes to the vestibular system. Light and electron microscopic examination were used to identify membrane permeability and define boundaries in the epithelial lining of the auditory and vestibular endorgans.

Perilymphatic Fistula: Historical Perspective

“…An alternative explanation is that cochlear aqueduct was patent in the study by Emmett and colleagues and not so in the Ritter and Lawrence study. Convincing reports by Duval and Sutherland, 21 and Asher and Sando 22 showed that horseradish peroxidase tracers injected into CSF of guinea pigs are transmitted to the scala tympani through the cochlear aqueduct and along cochlear and vestibular nerve fibers.…”

K⁺ Cycling and Its Regulation in the Cochlea and the Vestibular Labyrinth

“…This view is supported by the finding that K + is cleared rapidly from perilymph of scala tympani [Ohyama et al, 1998]. On the path toward the spiral ligament, K + crosses the basilar membrane, which provides little or no barrier to ions [Asher and Sando, 1981]. Sudden changes in the extracellular K + concentration that occur with sensory stimulation may be buffered by supporting cells nearby the hair cells.…”