Publication:

Asymptomatic unilateral lateral semicircular canal aplasia associated with a dilated vestibule

Lateral semicircular canal aplasia is a rare form of vestibular dysplasia. This is the last canal to be formed during the fetal period, becoming susceptible to isolated malformations. A 17-year-old male patient performed a magnetic resonance with a subsequent incidental finding of isolated, unilateral, lateral SCS aplasia associated with a dilated vestibule. He was asymptomatic and physical examination was unremarkable. Videonistagmography showed a diminished ipsilateral caloric response and ipsilateral v-HIT gains were normal. To the best of our knowledge, this is the first non-syndromic case of aplasia of the lateral SCS with no vestibular or audiological symptoms. This absence could be explained by compensation due to the congenital nature of this malformation.