MRI STUDY OF CAVUM SEPTI PELLUCIDI IN SCHIZOPHRENIA, AFFECTIVE-DISORDER, AND SCHIZOTYPAL PERSONALITY-DISORDER

Objective: A cavum between the septi pellucidi may reflect neurodevelo pmental anomalies in midline structures of the brain. The authors exam ined cavum septi pellucidi in subjects with schizophrenia, affective d isorder, and schizotypal personality disorder and in normal subjects. Method: Thirty schizophrenic patients (15 chronic, 15 first-episode), 16 patients with affective disorder (first-episode), 21 patients with schizotypal personality disorder, and 46 normal subjects were evaluate d with magnetic resonance imaging. Cavum septi pellucidi runs assessed by counting the number of 1.5-mm slices containing cavum septi pelluc idi. Results: The presence or absence of cavum septi pellucidi did not differentiate among groups. However, the prevalence of abnormal cavum septi pellucidi (i.e., cavum septi pellucidi contained on four or mor e slices) was 30.4% for schizophrenic patients (36.4% for chronic, 25. 0% for first-episode), 20.0% for patients with affective disorder, 18. 8% for patients with schizotypal personality disorder, and 10.3% for n ormal subjects. When the authors used the Nopoulos ef al. cl ire?ia fo r rating cavum septi pellucidi, which omitted borderline cases with ca vum septi pellucidi on three slices, the prevalence of abnormal cavum septi pellucidi increased to 35.0% for schizophrenia (40.0% for chroni c, 30.0% for first-episode), 25.0% for affective disorder, 27.3% for s chizotypal personality disorder; and 13.0% for normal subjects. There was a statistically significant difference in ratings between schizoph renic and normal subjects. Conclusions: The results suggest that alter ations in midline structures during the course of neurodevelopment may play a role in the pathogenesis of schizophrenia.