During a period of four years the authors experienced eighteen cases of focal seizure disorder, showing small ring or nodular enhancement with surrouding low density on CT scans. In fifteen cases, the epileptogenic lesions decreased in size or resolved completely on serial CT scans. Three cases were explored surgically. Males and famales were equally affected. Their age ranged from six to fourtyfive years and fifteen patients were under the age of thirty years. The principal symptoms and signs consisted of focal siezures (17 cases), generalized seizure during sleep (1 case), focal neurological deficits (14 cases), and intracranial hypertension (4 cases). The lesions of CT scans were found frequently in the parietal and frontal lobes. The clinical course of this self-limited disorder was variable and well correlated with the change of CT findings. The histological findings were the typical tuberculoma and the caseating gramuloma containing calcium in two cases. In one case the enhancing nodule of CT scan was not resected and the tissue specimen around the nodule revealed nonspecific inflammation. The cause of this disorder might be tuberculoma, but in some cases we could not rule out cysticercosis.