Section Editor: Sandy Cheng-Yu Chen, M.D.
Taipei Medical University Hospital, Taipei, Taiwan
Figure Caption
A, B, C - right inner ear; D, E, F - left inner ear
Enlarged vestibular aqueduct syndrome is the most common congenital inner ear anomaly, causing fluctuating and progressive hearing loss starting in early childhood. The hearing loss is often associated with intermittent episodes of ataxia. Bilateral anomaly is more frequent and is commonly associated with other inner ear anomalies. The classic MRI signs are: enlarged vestibules (blue arrows), enlarged vestibular aqueducts/endolymphatic ducts (green arrows) (when having a transverse width, at mid point, more than 1.5mm or being larger than the posterior semicircular canal), the presence of enlarged endolymphatic sacs (yellow arrows), and associated cochlear dysplasia (red arrows). The differential diagnosis is endolymphatic sac tumor in unilateral cases.