STRUCTURAL BRAIN ABNORMALITIES IN 1ST-EPISODE MANIA

Using magnetic resonance imaging (MRI), we studied brain morphometric differences between patients with first-episode mania (n = 17) and nor mal control subjects (n = 16). Patients were admitted for their first psychiatric hospitalization and met DSM-III-R criteria for bipolar dis order, manic or mixed. Diagnoses were made using the Structured Clinic al Interview for DSM-III-R. Patients and control subjects were matched for age, gender, height, past history of substance abuse, and handedn ess, although control subjects had attained higher levels of education . MRI inversion recovery coronal scans were used for measurements. Vol umetric measurements were obtained for cerebral hemispheres, lateral a nd third ventricles, caudate, thalamus, and cingulate gyrus. Patients with first-episode mania demonstrated significantly larger third-ventr icular volumes, possibly increased lateral ventricular volumes, and di fferences in gray/white matter distribution compared with normal contr ol subjects. The possible pathophysiologicical meaning of these findin gs is discussed.