Familial Superior Canal Dehiscence Syndrome

IMPORTANCE The etiology of superior canal dehiscence (SCD) involving the arcuate eminence is not completely understood, but genetic factors may play a role. One hypothesis is that patients are born with a defect of the superior canal, and an acute event (such as head trauma) or progressive loss of bone (eg, due to dural pulsations) may result in the onset of SCD symptoms. Familial SCD has only been briefly mentioned in the literature to date. OBSERVATIONS We report 3 families that each had 2 members with SCD syndrome. We found that first-degree relatives presented with similar complaints and that temporal bone computed tomography scans between relatives showed very similar skull base topography and anatomic SCD defects. CONCLUSIONS AND RELEVANCE The presence of symptomatic SCD among first-degree relatives and similar skull base topography suggests that geneticsmay play a role in the etiology of SCD.