BRAIN MORPHOLOGY ASSESSED BY COMPUTED-TOMOGRAPHY IN PATIENTS WITH GERIATRIC DEPRESSION, PATIENTS WITH DEGENERATIVE DEMENTIA, AND NORMAL CONTROL SUBJECTS

To determine whether patients with geriatric depression have specific alterations in brain morphology, internal (ventricles) and external (f rontal, temporal, and parieto-occipital) components of the cerebrospin al fluid (CSF) spaces were examined. Planimetric measurements of compu ted tomographic (CT) scans from patients with geriatric depression wer e compared with measurements from two age- and sex-matched control gro ups: normal control subjects and patients with primary degenerative de mentia. Scans of 34 patients (6 men, 28 women; mean age 70.7 years) wh o met DSM-III-R diagnostic criteria for major depression, 29 patients with DSM-III-R primary degenerative dementia (8 men, 21 women; mean ag e 71.2 years), and 43 nonpsychiatric control subjects (10 men, 33 wome n; mean age 70.8 years) were evaluated. The areas of the frontal and p arieto-occipital sulci, the Sylvian fissures, and the lateral and thir d ventricles were measured separately for the right and left hemispher es. Compared with the control subjects, patients with geriatric depres sion revealed a remarkable enlargement (up to 125%) of the left Sylvia n fissure on several levels and a more subtle enlargement of the ventr icles, cortical sulci, and right Sylvian fissure (20-50%). The lateral ity index differed significantly between depressed patients and normal control subjects (but not between the demented patients and the norma l control group) only for the Sylvian fissure. Demented patients showe d a considerable brain atrophy that affected all CSF components (enlar gment of 30-160%), but the left temporal region was less affected than in the depressed patients. Compared with the findings in geriatric de pression, ventricular enlargement was significant in dementia. In the group with geriatric depression, there was no correlation between CT p arameters and disease duration, The findings provide further evidence of alterations in brain morphology of patients with geriatric depressi on. The pattern of pathomorphology differs from that of demented patie nts.