The role of computed cranial tomography (CT) in epilepsy.

To evaluate the usefulness of CT in detecting unexpected brain lesions in epileptics, scan results were analyzed in a consecutive series of 196 adult epileptics in whom there was no known etiology for their seizures nor any abnormality on neurological examination. Nineteen additional epileptics, selected on the basis of an unexpected positive CT were also included for analysis. In the consecutive series, the overall incidence of abnormal scans was 16% with the highest yield (44%) found in patients with partial elementary seizures. Partial seizures secondarily generalized were correlated with a significantly higher CT positivity than purely partial seizures. Patients with seizures for less than six months more frequently showed CT abnormalities than patients with a longer history. In 25 of 51 cases with abnormal scans a specific lesion amenable to therapy was detected, including 16 neoplasms and 5 arteriovenous malformations. Other lesions included generalized or focal atrophy, infarcts, calcified lesions of tuberous sclerosis, unexplained calcifications and focal low-density or enhancing lesions.