Figure 4.

Examples of perfusion and permeability maps for a variety of histologically distinct intracranial tumours. Post-contrast T₁ weighted images and post-contrast T₁ weighted images with overlaid rCBV (cerebral blood volume) and K^trans maps for oligodendroglioma (O, grade II); there are focal increases in both rCBV and K^trans within the tumour (white arrows) when compared with normal appearing white matter; astrocytoma (A, grade II), both rCBV and K^trans within the tumour are similar to normal appearing white matter; anaplastic astrocytoma (AA, grade III), marked increase in K^trans and small increase in rCBV (white arrows) is seen within the tumour when compared with normal appearing white matter; glioblastoma multiforme (GBM, grade IV), the tumour exhibits both high rCBV and high K^trans within the solid enhancing component, with low/zero rCBV and K^trans within the necrotic core; metastasis (primary breast carcinoma), both rCBV and K^trans are elevated in comparison to normal appearing white matter; lymphoma, K^trans is elevated within the tumour mass while the rCBV remains similar to normal appearing white matter; and meningioma (grade I), the extremely high values of both rCBV and K^trans within the tumour in comparison to normal appearing white matter reflect the dural blood supply of the lesion, lying outside the blood–brain barrier. DCE, dynamic contrast enhanced; DSC, dynamic susceptibility weighted.