[HRCT findings in congenital aural atresia].

PURPOSE: To define high resolution computed tomography findings in the external, middle and inner ear of patients with congenital aural atresia and to emphasize the importance of these findings in the preoperative evaluation. MATERIALS AND METHODS: Twenty one patients with congenital aural atresia (14 male, 7 female) aged between 1-30 years were evaluated with high resolution computed tomography of the temporal bone. A Toshiba TCT-600 scanner was used in 11 cases, and a Xvision/GX scanner was used in 10 cases. Sections 1 mm thick were obtained in axial and coronal projections using high bone detail algorithms. Sagittal reformations were also made when necessary. RESULTS: Forty-two ears in 21 patients with congenital aural atresia were studied. These included 8 patients with high bilateral and 13 with unilateral congenital aural atresia in which 8 patients had right sided and 5 patients had left sided atresia. Stenosis of the external auditory canal was found in 11 ears, complete atresia was found in 13 ears, incomplete atresia was found in 1 ear. There was varied ossicular deformity in 18 ears. Anomalies of the stapes and oval window were found in 6 ears. An anteriorly located mastoid segment of the facial nerve canal was identified in 11 ears. An inferiorly located tympanic segment of the facial nerve canal was identified in 2 ears, and 3 ears had an abnormal posterior orientation of the mandibular condyles. Only 2 patients had associated inner ear deformity. CONCLUSION: High resolution computed tomography is an effective method for the evaluation of the anomalies of the external, middle and inner ear in patients with congenital aural atresia and for planning the surgical treatment.