High grade gliomas: The role of dynamic contrast-enhanced susceptibility-weighted perfusion MRI and proton MR spectroscopic imaging in differentiating grade III from grade IV

Abstract

BackgroundAdvanced MR imaging techniques provide physiologic information which complements the conventional MRI findings. PurposeTo evaluate the role of dynamic contrast-enhanced perfusion MRI and proton MR spectroscopy (MRS) in differentiating grade-III from grade-IV glioma. Results40 patients with preliminary diagnosis of glioma according to the conventional MRI study and the WHO classification and grading of glioma underwent dynamic MRI study which revealed, 19 patients (47.5%) are diagnosed as grade-III, and 21 cases (52.5%) are diagnosed as grade-IV. The tumor core relative cerebral blood volume (rCBV) was highly significant (P=0.000) in differentiating grade III from grade IV with cutoff value of 6,sensitivity of 90.5%, specificity of 68.4%, PVP of 76% and NPV of 86.7%.In proton MR spectroscopy, (CHo/Cr) ratio was significant in differentiating grade III from grade IV glioma (P=0.02), while CHo/NAA, NAA/Cr and MI/Cr ratios were not significant. ConclusionThe rCBV estimation and the metabolite ratios separately or in combination increase the sensitivity of grading of glioma rather than the conventional MRI.