Comparison of Cerebral Blood Volume and Vascular Permeability from Dynamic Susceptibility Contrast-Enhanced Perfusion MR Imaging with Glioma Grade
Meng Lawa,
Stanley Yanga,
James S. Babba,d,
Edmond A. Knoppa,b,
John G. Golfinosb,
David Zagzagc and
Glyn Johnsona
a Department of Radiology, NYU Medical Center, NY
b Department of Neurosurgery, NYU Medical Center, NY
c Department of Pathology, NYU Medical Center, NY
d Department of Biostatistics, Fox Chase Cancer Center, Philadelphia, PA

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FIG 1. Correlation analysis of rCBV, K trans, and glioma grade.
A, rCBV and glioma grade were strongly correlated, with Spearman r = 0.817 (P = .0001) and Pearson r = 0.771 (P = .0004). The slope and its gradient are consistent with a strong positive correlation with highly significant P values.
B, A weaker correlation was observed between K trans and glioma grade: Spearman r = 0.234 (P = .046) and Pearson r = 0.277 (P = .017). Although the slope indicates a positive correlation, its gradient is less pronounced, with less significant P values than in A. Furthermore, more overlap is noted in K trans measurements than in the rCBV measurements in A.
C, Relationship between rCBV and Ktrans is characterized by a modest yet statistically significant Spearman rank correlation (r = 0.266; P = .023) and a weak, statistically insignificant Pearson product moment correlation (r = 0.163; P = .168).
D, Receiver operating characteristic curves for rCBV and Ktrans, as estimated from logistic regression. rCBV was a significant predictor of high-grade gliomas with higher sensitivity and specificity than Ktrans.
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FIG 2. Low-grade astrocytoma (grade I/III).
A, T2-weighted image (3158/119) demonstrates bifrontal abnormalities in signal intensity centered primarily in the left frontal lobe.
B, Contrast-enhanced T1-weighted image (600/14/1) demonstrates an ill-defined focus of enhancement.
C, rCBV map demonstrates a few foci of mildly elevated perfusion (arrow), which are in a location different from the region of maximal enhancement in B.
D, SD25 color map suggests low permeability throughout the lesion.
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FIG 3. Anaplastic astrocytoma (grade II/III).
A, Proton densityweighted image (3158/17) demonstrates heterogeneous, left-sided paraventricular lesion extending into the left lateral ventricle. There is a small amount of vasogenic edema.
B, Contrast-enhanced T1-weighted image (600/14/1) demonstrates a small focus of peripheral enhancement.
C, rCBV map demonstrates elevated perfusion. On this occasion, the finding corresponds to the enhancing focus in B.
D, SD25 color map suggests intermediate permeability in the solid portions of this tumor.
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FIG 4. GBM (grade III/III).
A, T2-weighted image (3158/119/1) demonstrates a left parietal lesion with mass effect, edema, and signal-intensity heterogeneity. These are features of a high-grade glioma, such as a GBM.
B, Contrast-enhanced T1-weighted (600/14/1) with extensive, heterogeneous contrast enhancement.
C, rCBV map shows markedly elevated perfusion.
D, SD25 color map suggests markedly elevated permeability. Note that the areas of highest rCBV elevation do not directly correspond to the regions of highest SD25 (arrow).
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FIG 5. Typical normalized signal-intensity curves for the three glioma grades studied. Grade I glioma demonstrates a shallow perfusion signal-intensity curve with SD25 after the bolus peak; this was relatively close to the prebolus baseline, suggesting relatively low permeability. Grade II glioma demonstrates a more substantial initial signal intensity drop, indicating higher rCBV with slower return to baseline. SD25 is considerably larger than that seen in grade I gliomas. Grade III glioma shows a larger area above the curve, indicating high rCBV with a similarly delayed return to baseline; this suggests high permeability.
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