Comparison of cerebral blood volume and vascular permeability from dynamic susceptibility contrast-enhanced perfusion MR imaging with glioma grade

BACKGROUND AND PURPOSE: Relative cerebral blood volume (rCBV) and vascular permeability (K^trans) permit in vivo assessment of glioma microvasculature. We assessed the associations between rCBV and K ^trans derived from dynamic, susceptibility-weighted, contrast-enhanced (DSC) MR imaging and tumor grade and between rCBV and K ^trans. METHODS: Seventy-three patients with primary gliomas underwent conventional and DSC MR imaging, rCBVs were obtained from regions of maximal abnormality for each lesion on rCBV color maps. K^trans was derived from a pharmacokinetic modeling algorithm. Histopathologic grade was compared with rCBV and K^trans (Tukey honestly significant difference). Spearman and Pearson correlation factors were determined between rCBV, K^trans, and tumor grade. The diagnostic utility of rCBV and K^trans in in discriminating grade II or III tumors from grade I tumors was assessed by logistic regression. RESULTS: rCBV was significantly different for all three grades (P ≤ .0005). K^trans was significantly different between grade I and grade II or III (P = .027) but not between other grades or combinations of grades. Spearman rank and Pearson correlations, respectively, were as follows: rCBV and grade, r = 0.817 and r = 0.771; K^trans and grade, r = 0.234 and r = 0.277; and rCBV and K ^trans, r = 0.266 and r = 0.163. Only rCBV was significantly predictive of high-grade gliomas (P < .0001). CONCLUSION: rCBV with strongly correlated with tumor grade; the correlation between K^trans and tumor grade was weaker. rCBV and K^trans were positively but weakly correlated, suggesting that these parameters demonstrate different tumor characteristics. rCBV is a more significant predictor of high-grade glioma than K^trans.