Congenital anomalies of the temporal bone.

Inner ear anomalies are a rare but important cause of sensorineural hearing loss. Combined external and middle ear anomalies are more common, causing conductive hearing loss and cosmetic deformity. The course of the facial nerve canal is altered in many temporal bone anomalies. Its location is of great importance when surgical therapy is anticipated. Vascular anomalies and bone dysplasias occasionally affect the temporal bone. High resolution CT, using thin sections and edge enhancement techniques, is capable of demonstrating the finer bony details of these temporal bone anomalies.