Figure 1a: Conventional MR images and rCBV map in 37-year-old man with biopsy-proved World Health Organization grade III astrocytoma. (a) Transverse contrast-enhanced T1-weighted image shows inhomogeneous mass in right frontal lobe. Anterior portion of the mass (arrowhead) shows contrast enhancement; posterior half of the mass does not. (b) Baseline transverse echo-planar T2*-weighted image from DSC sequence (precontrast) shows homogeneous hyperintense signal throughout the mass. (c) rCBV map shows that anterior portion of the mass (corresponding to contrast-enhanced portion in a) has high rCBV (red and yellow), and posterior portion has low rCBV (blue).