EVALUATION OF BRAIN-TUMORS BY POSITRON EMISSION TOMOGRAPHY

The clinical application of positron emmission tomography (PET) for the evaluation of brain tumours has proved clinically valuable. Amino acid and FDG-glucose PET provide information on thc degree of malignancy and thc prognosis during the initial evaluation. After therapy, the residual tumour can bc visualized and recurrence can be differentiated from necrosis. Amino acids have advantages over FDG for these clinical applications. Blood flow, oxygen extraction and metabolism and blood-brain harrier permeability are of minor relevance in clinical situations. Comparison of PET with MRI and MRS will provide new data. The quantitative information of the unique information yielded by PET will lead to a more important clinical role, as will thc extrapolation of this experience to the SPECT technique.