Sound- and/or Pressure-Induced Vertigo Due to Bone Dehiscence of the Superior Semicircular Canal

Abstract

VESTIBULAR responses to sound and/or pressure transmitted to an inner ear were initially documented in studies during the first quarter of this century. The Tullio phenomenon is vertigo or other abnormal vestibular sensations accompanied by eye and/or head movements in response to sound. In the initial experimental studies by Tullio,¹ later elaborated by Huizinga² and Eunen et al,³ fenestration of individual semicircular canals in pigeons led to sound-evoked eye and head movements in the plane of these canals. These responses were abolished by application of cocaine to the ampulla of the fenestrated canal. It was further noted that sound-evoked eye movements could be produced without surgical interventions on the labyrinth when greater intensity stimuli were used. Young et al⁴ subsequently showed that vestibular nerve afferents in the squirrel monkey respond to sound with phase-locking thresholds typically higher than 100-dB sound pressure level and rate-change thresholds 10 to 30 dB higher than intensities required for phase locking.