CEREBRAL BENZODIAZEPINE RECEPTORS IN HIPPOCAMPAL SCLEROSIS - AN OBJECTIVE IN-VIVO ANALYSIS

We objectively delineated the extent of abnormalities in central benzo diazepine receptor (cBZR) binding using [C-11]flumazenil (FMZ)-PET and high resolution volumetric MRI in 12 patients with mesial temporal lo be epilepsy (mTLE) associated with unilateral hippocampal sclerosis, w ho underwent presurgical evaluation and subsequent temporal lobe surge ry. We compared parametric 3D-images of regional cerebral [C-11]FMZ vo lume of distribution (V-d) obtained from individuals and groups of pat ients with [C-11]FMZ-V-d from a group of 17 healthy controls using sta tistical parametric mapping (SPM). The [C-12]FMZ-V-d was significantly reduced (P < 0.001) in the affected hippocampus in the group of 12 pa tients with unilateral hippocampal sclerosis. Analysis of individual p atients reflected the group finding and there was no significant abnor mality of cBZR binding outside the hippocampus in any patient. We conc lude that SPM is an useful objective method for detecting changes in r egional cerebral [C-11]FMZ binding and that in patients with mTLE and unilateral hippocampal sclerosis reduction of cBZR binding is restrict ed to the area of hippocampal sclerosis with no abnormalities being de tected in the temporal neocortex or elsewhere in the neocortex.