| Summary: | Purpose: To provide new insights into a potential mechanism of sudden sensorineural hearing loss (SSNHL) in superior semicircular canal dehiscence (SCD). Materials and methods: This study is a retrospective case series of three adult subjects who presented with acute SSNHL and vestibular symptoms, with computed tomography (CT) findings suggestive of SCD. Subjects were evaluated with magnetic resonance imaging (MRI) and computed tomography (CT) imaging of the temporal bone along with audiometric and vestibular testing. Appropriate medical intervention was offered, and surgical intervention was discussed with all patients. Main outcome measures included clinical symptoms, audiometry, vestibular testing, cervical vestibular evoked myogenic potentials, and imaging. Results: All three patients had sudden onset of symptoms, with audiometry consistent with SNHL and imaging demonstrating SCD. One patient recovered normal hearing after intratympanic steroid injections. Conclusions: These cases represent an unusual presentation of possible SCD and may represent a new, unrecognized etiology of SSNHL. These cases suggest that there may be utility in offering CT scans of the temporal bone in the setting of sudden hearing loss when MRI is negative and vestibular symptoms persist. Rupture of the underlying membranous labyrinth may provide a plausible explanation for the presentation of SSNHL with the onset of SCD symptoms. Keywords: Superior semicircular canal dehiscence, Sudden sensorineural hearing loss, Third window
|
|---|
