Value of CT scan in the diagnosis of temporal bone diseases in children.

CT scan of the temporal bone has become a frequently ordered test for diagnosis of temporal bone pathology. We retrospectively examined our experience with CT scans of the temporal bones in 124 consecutive children from January 1983 to September 1984 in an attempt to assess its usefulness in diagnosis and treatment of ear disease in children. Patients were divided into six categories according to their pre-scan diagnosis, (trauma, congenital aural atresia, dizziness, facial nerve paralysis, middle ear disease, congenital sensorineural hearing loss) and CT findings were compared to data found by physical examination, by otologic studies such as audiogram and BSER, by other x-ray studies and ultimately compared to findings at surgery when applicable. CT was found to be instrumental in diagnosing middle ear disease; gave necessary preoperative information in children with aural atresia; delineated most temporal bone fractures; ruled out gross inflammatory, neoplastic, or traumatic etiologies in dizzy patients and in facial nerve abnormalities; and provided anatomic information about the inner ear in patients with sensorineural hearing loss. In our group of patients with sensorineural hearing loss, a 6.8% incidence of anatomic malformations was found by CT. However, CT had major limitations in stapes and oval window areas, especially in cases of perilymph fistulas. CT use was also limited in children because of the difficulty in achieving projections that require active patient cooperation.