Aural atresia. Axial CT images (a)–(c) demonstrate abnormal facial nerve canal tympanic segment coursing posterolaterally to the middle ear cavity (arrows), instead of the normal posteromedial course. Coronal CT image (d) demonstrates the abnormal proximal tympanic segment of the facial nerve canal coursing superior to the middle ear cavity and ossicles (arrow), instead of its normal medial course. Coronal CT images (e)-(f) showing the abnormal distal tympanic segment and second genu of the facial nerve canal (arrows).
