VOLUMETRIC MRI OF THE LIMBIC SYSTEM - ANATOMIC DETERMINANTS

The limbic system comprises the hippocampal formation, fornix, mamilla ry bodies, thalamus, and other integrated structures. It is involved i n complex functions including memory and emotion and in diseases such as temporal lobe epilepsy. Volume measurements of the amygdala and hip pocampus have been used reliably to study patients with temporal lobe epilepsy but have not extended to other limbic structures. We performe d volume measurements of hippocampus, amygdala, fornix and mamillary b odies in healthy individuals. Measurements of the amygdala, hippocampu s, fornix and mamillary bodies revealed significant differences in vol ume between right and left sides (P < 0.001). The intraclass coefficie nt of variation for measurements was high for all structures except th e mamillary bodies. Qualitative image assessment of the same structure s revealed no asymmetries between the hemispheres. This technique can be applied to the study of disorders affecting the limbic system.