Fig 2.

A, Measures of rCBV show poor correlation with MVD under conditions of high vessel size heterogeneity (n = 18, black data series) but good correlation (red data series) when limiting analysis to homogeneous vessel size (n = 20, red series). This “conditional correlation” suggests that rCBV is an unreliable measure of MVD in human HGG, which commonly demonstrates high vessel size heterogeneity. B, MVA strongly correlates with rCBV for both high (n = 18, black series) and low (n = 20, red series) vessel size–heterogeneity groups, suggesting the clinical robustness of rCBV to quantify vessel area in human HGG. Of note, the 6 rightmost data points were measured from 6 different patients.