SPET IMAGING OF INTRACRANIAL TUMORS WITH TC-99(M)-SESTAMIBI

Single photon emission tomography (SPET) employing Tc-99(m)-sestamibi (MIBI) injected intravenously was performed in 27 patients for pre-sur gical evaluation of intraparenchymal brain tumours. A computerized tom ography (CT) scan was performed in 26 patients, magnetic resonance ima ging (MRI) in 8 patients and digital subtraction angiography (DSA) in 14 patients. Visual analysis of the SPET scans was performed using a 4 -point scale relating to background activity, to evaluate MIBI uptake in the tumour. The vascular supply and the cellular component were als o evaluated using DSA and CT scans. In normal controls, MIBI uptake wa s observed in the scalp, in the choroid plexus and in the pituitary gl and, but never in normal parenchyma. Among the astrocytoma group of pa tients, a trend between MIBI uptake and grade of tumour was noted. MIB I uptake in meningiomas depends primarily on the vascular supply. Our results support the hypothesis that vascular supply, integrity of the blood-brain barrier, the degree of malignancy of the neoplasm and the viability of the tumour cells may be related to MIBI uptake.