VOLUMETRIC FINDINGS IN LATE-ONSET DEPRESSION - A STUDY WITH QUANTITATIVE MAGNETIC-RESONANCE-IMAGING

A number of observations including clinical manifestation, course, out come, and family history, support the view that patients presenting wi th a major depression occurring first in late life should be treated a s a nosological subgroup. In this study quantitative magnetic resonanc e imaging (MRI) was used to investigate volumes of different brain str uctures in 19 patients with late onset major depression (age of onset >50) and 13 age matched controls. 3-D MRI sequences were acquired usin g a Siemens 1.5T scanner. Whole brain volume, CSF volume, volume of th e frontal and temporal lobes and the volume of the amygdala-hippocampu s complex were assessed using the software NMRWin. Compared to the con trols, depressed patients showed a significantly lower whole brain vol ume and a significantly higher CSF volume, whereas volumes of the fron tal and temporal lobes as well as the amygdala-hippocampus complex vol umes were not significantly decreased. In addition, depressed patients exhibited a higher ventricle-brain ratio suggesting a higher degree o f central atrophy compared to healthy individuals. Our results indicat e that cerebral changes involving subcortical structures are of releva nce in the pathogenesis of late-onset depression. Defining the aetiolo gy of these lesions may be important for the development of preventive treatment of depression in the elderly.