Fig 5. Hypoperfused tumor on ASL. Axial (left) and coronal (center) gadolinium-enhanced T1-weighted images demonstrate a heterogeneously enhancing mass invading the third and lateral ventricles (yellow arrows). ASL (right) shows regional hypoperfusion within the more cystic portion of the tumor (white arrow). The solid portions show hyperperfusion on ASL (arrowhead). The tumor proved to be a pituitary macroadenoma at surgery.