Ten patients, who underwent computerized tomography (CT) study during evaluation for first episode schizophreniform psychosis were restudied an average of 7 years later. Of the 10 patients, 7 were found to carry a diagnosis of schizophrenia at follow-up. In this subgroup, there was no significant change in the mean ventricular brain ratio measure of cerebral ventricular size between the index and follow-up scans. These findings are consistent with the hypothesis that ventricular enlargement is present at the onset of schizophrenia and does not progress with duration of illness or treatment.