To correlate perfusion MR imaging with histologic grade of cerebral gliomas.
Materials & Methods
Relative cerebral blood volume (rCBV) maps were determined in 22 patients with
pathologically proved gliomas (11 glioblastomas, 8 anaplastic gliomas and 2 low-grade
gliomas) by dynamic contrast-enhanced T2*-weighted MR imaging. MR examination
was completed with conventional T1- and T2-weighted imaging. The rCBV maps were
calculated with an independent workstation by fitting a gamma-variate function to the
contrast material concentration versus time curve. Relative CBV ratios obtained between
tumor and normal white matter were compared between glioblastomas, anaplastic
gliomas and low-grade gliomas by means of receiver operating characteristic (ROC)
analysis.
Results
Mean rCBV ratios were 4.85 (\ub1 1) for glioblastomas, 3.87 (\ub1 0.7) for anaplastic gliomas
and 1.65 (\ub1 1.6) for low-grade gliomas. Receiver operating characteristic analysis
demonstrates significant differences between glioblastomas and anaplastic gliomas
(p<.05), between anaplastic gliomas and low-grade gliomas (p<.05) and between
glioblastomas and low-grade gliomas (p<.01). The rCBV ratio cutoff value between highgrade
gliomas and low-grade gliomas was 2.52 with a sensitivity and specificity of 100%
and 75% respectively.
Conclusion
Perfusion MR imaging is a reliable technique for differentiating high-grade from low-grade
glioma