Comparison of cerebral blood volume and permeability in preoperative grading of intracranial glioma using CT perfusion imaging

Abstract

Introduction: Regional cerebral blood volume (rCBV) and permeability surfaces (rPS) permit in vivo assessment of glioma microvasculature, which provides quite important pathophysiological information in grading gliomas. The aim of our study was to simultaneously examine rCBV and rPS in glioma patients to determine their correlation with histological grade using CT perfusion imaging.

Methods: A total of 22 patients with gliomas underwent multislice CT perfusion imaging preoperatively. Low-grade and high-grade groups were categorized corresponding to WHO grade II gliomas and WHO grade III or IV gliomas, respectively, as determined by histopathological examination. rCBVs and rPSs were obtained from regions of maximal abnormality in tumor parenchyma on CBV and PS color perfusion maps. Perfusion parameters were compared using the Kruskal-Wallis test in order to evaluate the differences in relation to tumor grade. The Pearson coefficients of rCBV and rPS for each tumor grade were assessed using SPSS 13.0 software.

Results: rCBV and rPS provided significant P-value in differentiating glioma grade (low-grade gliomas 3.28+/-2.01 vs 2.12+/-3.19 ml/100 g/min, high-grade gliomas 8.87+/-4.63 vs 12.11+/-3.18 ml/100 g/min, P<0.05). Receiver operating characteristic (ROC) curves revealed better specificity and sensitivity in PS than in CBV for glioma grade. A significant correlation between rCBV and rPS was observed in high-grade gliomas (r=0.684). rCBVs in oligodendrogliomas were higher than in other low-grade gliomas, whereas their rPS values did not show a parallel difference.

Conclusion: Perfusion CT provides useful information for glioma grading and might have the potential to significantly impact clinical management and follow-up of cerebral gliomas.