Isolated Enlarged Endolymphatic Sac Causing Sensorineural Hearing Loss: A Case Report

Abstract

This is the case of a healthy 10-year-old girl presenting to the pediatric otolaryngology clinic for an incidental finding of a 20 mm dilatation within the left posterior fossa on brain computed tomography done for evaluation of left retro-auricular pain. Comprehensive audiometry showed left sensorineural hearing loss at low frequencies. Magnetic resonance imaging revealed a cystic lesion along the posterior aspect of the left temporal bone with normal inner ear anatomy consistent with an enlarged endolymphatic sac anomaly. This pathology is a rare entity with only one previously reported case in the literature.

Keywords: endolymphatic sac; hearing loss; otology; pediatric otolaryngology; sensorineural.