RESUMEN
Congenital anomalies of the inner ear in comparison with anomalies of the external and middle ear present a clinical problem for diagnosis, because the inner ear structures can not be observed directly. Ontolaryngologists can diagnose these anomalies by radiological study alone. In recent years, high-resolution computed tomographs permits more reliable and definitive diagnosis of these anomalies. Although the incidence of anomalies of the vestibular canals have been less well studied than those of cochlear anomalies, congenital malformation of the semicircular canals are rare. We present one case with computed tomographic findings of lateral semicircular canal dysplasia with normal cochlea development. Initial air and bone conductions were within normal limits, although he mainly complained dizziness. Bithermal caloric responses were absent on the involved side. Computed tomogram showed isolated lateral semicircular canal dysplasia. To our knowledge, this case is the first report of labyrinthine dysplasia with normal cochlear development in Korea.