Perception of Audio-frequency Vibrations by Profoundly Deaf Subjects after Fenestration of the Vestibular System

Abstract

A survey is given of the literature on the sensitivity of the vestibular system to audio-frequency sound and vibration in animals. It is also shown that responses to such stimuli can be evoked in man. On the basis of these results it was decided to perform a fenestration of the horizontal semicircular canal in three profoundly deaf volunteers, with normal sensitivity of the vestibular system. The first results are promising: the threshold for audio-frequency vibration in the operated ears improved markedly. Furthermore, the subjects reported perception of environmental sounds using a bone conductor hearing aid.

The Effect of Noise Exposure in the Presence of Canal Fenestration on the Amplitude of Short-Latency Vestibular Evoked Potentials

“…9 These clinical and surgical findings provide additional support for the suggestion that fenestration or dehiscence of a SCC allows sound and pressure stimuli to reach and affect the vestibular end organs. In fact, Ribaric et al 21,22 have taken clinical advantage of this by fenestrating the SCC in patients with profound hearing loss and normal vestibular function, hoping that such a procedure would enable the patients to make use of the vestibular end organs to perceive sound stimuli. Following fenestration, the patients reported improved hearing to bone-conducted, not air-conducted, stimuli.…”

Effects of microwaves (900 MHz) on the cochlear receptor: exposure systems and preliminary results

“…as a buzzing, clicking, hissing or popping noise, according to the various characteristics of the field modulation [2]. Moreover, some physiological changes have been observed in rats after exposure to low levels of microwaves [3].…”

Semicircular Canal Pressure Changes During High-intensity Acoustic Stimulation

“…Ribaric et al (1992) fenestrated the lateral semicircular canal in profoundly deaf patients with normal vestibular function and demonstrated improved perception of bone-conducted sounds. 21,22 Like fenestration, semicircular canal dehiscence also effectively opens the bony labyrinth and can lead to sound-evoked vestibular symptoms including vertigo and oscillopsia. Mechanistically, the dehiscence serves as a mobile third window so that endolymphatic motion causes excitatory cupula deflection within the superior semicircular canal stimulating vestibular nerve afferents that cause a vertical torsional nystagmus.…”