Third and lateral ventricular volumes in schizophrenia: support for progressive enlargement of both structures.

Third and lateral ventricular enlargement exists in a subgroup of schizophrenic patients. It is unclear, however, whether these abnormalities consistently coexist in the same patients or represent distinct pathologies. Whether these changes are static or progressive in nature is also unresolved. Third and lateral ventricular volumes (magnetic resonance imaging, total volumes calculated on complete coronal series) were examined in controls (n = 20) and schizophrenic patients (n = 20). Third ventricular, but not lateral ventricular, volume was increased in patients. Ventricular intercorrelations differed significantly between patients and controls. Ventricular measures were more highly correlated in patients than in controls. Age was also significantly more positively correlated with ventricular measures in patients. Results replicate the finding of third ventricular enlargement in some schizophrenic patients. The high correlation between lateral and third ventricular size in schizophrenic patients suggests a pathologic process affecting both structures. Enlargement of both third and lateral ventricles may be more specific to schizophrenic patients than enlargement of either structure alone. The data also indirectly support progression of ventricular enlargement.