Perfusion CT Imaging of Brain Tumors: An Overview

PCT maps in a 50-year-old man with glioblastoma multiforme. The CBV map shows high blood volume (CBV = 4.56 mL/100 g), and the PS map shows high permeability (PS = 3.78 mL/100 g/min) along the enhancing nodular margins of the tumor (arrow). Inset: Postcontrast T1-weighted image shows a heterogeneously enhancing mass with irregular central necrosis in the right parietal region.

PCT maps in a 39-year-old woman with heterogeneously enhancing grade III glioma involving the left temporal lobe. CBV and PS maps show an enhancing region laterally. Region of interest 7 demonstrates the highest PS (8.52 mL/100 g/min), but not the highest CBV (4.73 mL/100 g) within the tumor; whereas region of interest 8 shows relatively lower PS (1.14 mL/100 g/min) but the highest CBV within the tumor (11.65 mL/100 g), suggesting that there is marked heterogeneity within high-grade gliomas, which could be due to the heterogeneity of tumor angiogenesis. Inset: Postcontrast T1-weighted axial images show a heterogeneously enhancing left temporal lobe tumor.

A, A 56-year-old man who was previously treated for a right occipital anaplastic astrocytoma, shows a progressive enhancing lesion in the medial aspect of the surgical resection cavity (inset) and PCT CBV map shows high CBV (CBV = 3.5 ml/100 g), suggesting recurrent/progressive tumor (arrows). B, Histopathology proven radiation/treatment necrosis (arrows) in a 34-year-old woman who underwent radiation and chemotherapy for a right fronto-parietal anaplastic astrocytoma shows low CBV (CBV = 1.1 ml/100 g) in a recurrent/progressive enhancing lesion (inset).

A, Same case as in Fig 4A. PCT PS map shows high PS (PS = 4.2 ml/100 g/min) in the medial aspect of the surgical resection cavity (arrows) in a histopathology proven recurrent/progressive tumor (inset). B, A 41-year-old man with initial diagnosis of WHO grade II astrocytoma received chemotherapy and radiation. A 33 month follow-up MR image (inset) shows development of a recurrent enhancing lesion. PCT PS map shows low PS (PS = 1.1 ml/100 g/min) suggesting radiation necrosis. The patient underwent open biopsy and histopathology revealed radiation necrosis without viable tumor cells.

Histopathology-proved TDL in a 45-year-old woman who presented with a very heterogeneously enhancing large lesion in the left frontoparietal periventricular region (inset). PCT CBV and PS maps show low to minimally increased blood volume (CBV = 1.01 mL/100 g) and permeability (PS = 0.40 mL/100 g/min), unlike a high-grade tumor that it was mimicking on postcontrast images, hence, suggesting a non-neoplastic lesion.