CARBON-11-METHIONINE AND FLUORINE-18-FDG PET STUDY IN BRAIN HEMATOMA

Three patients were examined using PET with L-methyl-C-11-methionine ( C-11-methionine) and 2-F-18-fluoro-2-deoxy-D-glucose (FDG) 20 to 32 da ys after the occurrence of nontumoral brain hematomas. PET revealed hi gh uptake of C-11-methionine in the area surrounding the hematoma in a ll three patients. In two patients, discrete spots of moderate uptake of FDG were found at the periphery of a hypometabolic area. PET studie s were repeated in two patients 76 and 103 days after the bleeding, re spectively, and showed a dramatic decrease in C-11-methionine uptake a round the hematoma. The spots of FDG uptake disappeared on the repeate d late scans. We hypothesize that the subacute gliotic reaction surrou nding brain hematomas is responsible for increased uptake of C-11-meth ionine and for the presence of spots of FDG uptake. PET studies with C -11-methionine and FDG performed 20 to 32 days after the initial sympt om are not helpful in the differentiation between neoplastic and non-n eoplastic origins of an intracerebral hemorrhage since tracer uptake a t the periphery of the lesion may be increased in both.