[Temporal bone CT in the diagnosis of acquired diseases of the external auditory canal].

CT was used to examine 50 patients (100 temporal bones) aged 10 days to 60 years who had no signs of lesion of the external auditory canal (EAC) and 23 patients (27 temporal bones) aged 13 to 65 years who had clinical manifestations of acquired stenosis or obturation of the EAC. Polypositional CT of the temporal bone is the most informative technique of visualization of the osseous part of the EAC, at the same time the anterior and posterior EAC walls were evaluated in the axial projection and the upper and lower EAC walls were assessed in the coronary projection. According to CT data, formation of the osseous part of the EAC occurs within the first 7 years of a child's life. In the presence of EAC changes, CT may assess their pattern (a soft tissue or osseous one), their magnitude and location along the walls of the canal, the tympanic membrane, and other structures of the temporal bone. CT reveals the causes of acquired EAC obturation, stenosis, and atresia: osteocartilaginous exostoses, osteomas, polyps of the EAC, tumors of the temporal bone, as well as obturative keratosis and posttraumatic stenosis of the EAC. The detected EAC changes determine further management policy in a patient.