REGIONAL CEREBRAL BLOOD-VOLUME OF INTRACRANIAL TUMORS DETERMINED BY MRI

The aim of this study was to characterize intracranial tumors based on MR measurements of regional cerebral blood volume. In 8 patients with out intracranial pathology and 42 patients with intracranial tumors a T2-weighted image series was acquired during bolus injection of gadol inium-DTPA, and regional cerebral blood volume maps were calculated. T he regional cerebral blood volume index (rCBV(i)) of vital tumor was e xpressed in percent of the value measured in contralateral gray matter . In extra-axial tumors (meningiomas) rCBV(i) was higher (124 +/- 110 %), and in low-grade intra axial tumors rCBV(i) was lower (79 +/- 65 % ), than in contralateral cortex. In malignant intra-axial tumors the d istribution of rCBV was heterogeneous: high in vital tumor (glioblasto mas: rCBV(i) = 165 +/- 85 %; metastases: rCBV(i) = 106 +/- 79 %), but law in necrosis (rCBV(i) = 33 % of contralateral white matter) and ede ma (rCBV(i) = 53 % of contralateral white matter), rCBV(i) was highest in arteriovenous malformations (1053 +/- 584 % of contralateral gray matter). We conclude that regional cerebral blood volume and the degre e of heterogeneity of blood volume distribution is useful to character ize intracranial tumors, although the large biological variability of individual tumor entities indicates limitations.