A computerized tomographic evaluation of brain morphology in first episode psychotic patients

A growing body of computerized tomography (CT) research suggests that a significant proportion of schizophrenic patients have enlargement of the third and lateral cerebral ventricles and of the cortical sulci. Preliminary results indicate that these anomalies are present at the onset of schizophrenia and are associated with variables putatively linked to poor prognosis. Evidence of ventricular dilation in nonschizophrenic psychotic patients suggests that these morphological anomalies are not specific to the diagnosis of schizophrenia. There is much variability in the estimated prevalence of ventricular and sulcal dilation and several recent studies report no enlargement. Differences between studies in methodology, in the severity of illness of the patients, and in control group selection have been proposed as probable biases contributing to inconsistencies in the research literature. The purpose of the present study was to test a number of hypotheses suggested by the previous research. The first three predict that first episode schizophrenic and nonschizophrenic psychotic patients have 1. Enlarged lateral ventricles, 2. Enlarged third ventricle, and 3. Dilated cortical sulci. The fourth hypothesis predicts that these three brain anomalies are associated with variables putatively linked to poor prognosis (poor premorbid adjustment, negative symptoms, disrupted smooth-pursuit eye movements). The fifth hypothesis predicts that medical patients chosen from radiology records have smaller ventricles and sulci than do healthy control subjects. Measurements were taken from the CT scans of a representative sample of carefully diagnosed first episode, functionally psychotic patients. There were 31 schizophrenic, 20 schizo-phreniform, 18 bipolar, 16 depressed, three paranoid, and three schizoaffective patients. A volunteer control group of 44 healthy individuals was used for comparison. In order to evaluate possible biases due to the type of control subjects that are used, a second group comprised of 30 medical patients was obtained from radiology records. The results of this study indicate significant enlargement of the third ventricle in schizophrenic patients but failed to detect significant lateral ventricular enlargement or cortical atrophy in this patient group. No brain anomalies were found in schizophreniform, bipolar or depressed patient groups and no significant association was found between variables putatively associated with poor prognosis and any brain measure for any patient group. The third ventricle and cortical sulci were significantly smaller in the medical group than in the volunteer control group. The results are discussed in terms of the implications they have for previously reported findings and for future research. The present findings also underscore some methodological difficulties associated with using medical control subjects.Arts, Faculty ofPsychology, Department ofGraduat