FIG 4. Low-grade tumor: injected dose, 0.3 mmol/kg.

A, T2-weighted image (2300/85/1) in a 22-year-old woman shows a large mass in the right insular region (white arrow). The dark dots are flow voids from the branches of the middle cerebral artery (black arrow).

B, rCBV map shows low values in the tumor (arrow), even below those of adjacent white matter. The lesion was confirmed to be a WHO grade II glioma.