Superior semicircular canal dehiscence syndrome: a new aetiology

We report what we believe to be a unique aetiology of the superior semicircular canal dehiscence syndrome, a recently described condition in which vestibular imbalance and/or hearing loss results from the loss of continuity of the bone overlying the superior semicircular canals.

A 58-year-old woman presented with autophony in the right ear and momentary imbalance when shouting (Tullio phenomenon). Temporal bone computed tomography revealed a defect of the right superior semicircular canal caused by an enlarged superior petrosal sinus receiving drainage from a large cerebellar developmental venous anomaly.

We review superior semicircular canal dehiscence syndrome and its management, and we discuss common aetiologies, contrasting these with the unusual aetiology presented here. We conclude that superior semicircular canal dehiscence syndrome may present with a solely developmental aetiology, despite presenting late in life.