Computed tomography of the brain morphology of patients with first-episode schizophrenic psychosis.

OBJECTIVE: To report computed tomographic (CT) scan ratings of various aspects of brain morphology of a large representative sample of patients with a first episode of schizophrenic psychosis and to compare these ratings with those from a previously reported sample of patients with chronic schizophrenia.
METHODS: A brain CT scan was performed on 114 patients with a diagnosis of first episode of schizophrenia or schizophreniform psychosis. Ratings on sulcal and ventricular enlargement and sylvian fissure were obtained using the Computed Tomographic Rating Scale for Schizophrenia. The influence of age, sex, age of onset, duration of illness and clinical psychopathology on CT ratings was assessed using bivariate correlations and multiple regression analyses. The CT ratings were also compared with those from a sample of patients with chronic schizophrenia.
RESULTS: First-episode patients showed a modest enlargement of sulci and ventricles and a reversed asymmetry of the sylvian fissure. Age was the only independent predictor of these regional changes. Clinical symptoms, sex or duration of untreated psychosis showed no relation to CT ratings. A comparison of first-episode patients with chronically ill patients, with the effect of age covaried, revealed the sylvian fissure was significantly larger (right and left sides) in the chronically ill patients.
CONCLUSIONS: Patients with a first episode of schizophrenic psychosis showed evidence of morphological changes generally associated with chronic schizophrenia. Such changes are not likely related to sex, clinical symptoms or duration of untreated psychosis, but are influenced by age. Changes in the ventricles and sulcal size are unlikely to be progressive, suggesting a neurodevelopmental origin, whereas changes in the area of the sylvian fissure may be of a more degenerative nature.