Purpose : To evaluate the utility of dynamic contrast-enhanced T2**-weighted MR imaging in assessing thecerebral blood volume (CBV) in intra-axial brain tumors. Materials and Methods : Ten malignant gliomas (fiveglioblastomas, three anaplastic astrocytomas, two anaplastic oligodendrogliomas), five metastatic tumors and threehemangioblastomas were included in this study. In conjunction with T1- and T2-weighted imagings, all patientsunderwent dynamic contrast-enhanced T2*-weighted imaging, using the conventional gradient-echo technique(TR/TE/flip angle: 40/26/10o; 64x128 matrix; 5-6 mm thickness) during the bolus injection of 15 mmol/kg Gd-DTPA.From these dynamic images, CBV was calculated on a pixel-by-pixel basis and a CBV map was obtained. The CBVs ofthe tumor and contralateral normal white matter were measured by placing the ROI on the CBV map. The CBV ratios oftumor/normal white matter were compared among the three tumor groups. Results : CBV maps were successfully createdin all cases. CBV ratios varied from 1.7 to 13.0 (mean 6.1) in malignant gliomas, from 3.9 to 11.4 (mean 7.3) inmetastatic tumors and from 17.8 to 26.4 (mean 22.2) in hemangioblastomas (malignant gliomas vs hemangioblastomas,p<.05; metastatic tumors vs hemangioblastomas, p<.05; and malignant gliomas vs metastatic tumors, p>.05).Conclusion : Hypervascular hemangioblastomas have the highest CBV, and this allows for easy differentiation frommalignant gliomas and metastatic tumors. Both show a similar, moderately increased range of CBV suggesting thatthere is no significant difference in vascularity between the two tumor groups. Dynamic contrast-enhanced T2*imaging is a clinically useful technique which provides information about tumor vascularity not provided by standard MRI techniques.