Grading of Glioma Tumors by Analysis of Minimum Apparent Diffusion Coefficient and Maximum Relative Cerebral Blood Volume

Background: Gliomas are the most common primary neoplasms of the central nervous system. Relative cerebral blood volume (rCBV) could estimate high-grade Gliomas computed with dynamic susceptibility contrast MR imaging which it is artificially lowered by contrast extravasation through a disrupted blood-brain barrier. Objectives: Our intent was to clarify the usefulness of diffusion-weighted magnetic resonance imaging (DWI) and perfusion weighted magnetic resonance imaging (PWI) in the grading of Gliomas. Materials and Methods: Both PWI and DWI with a three-tesla scanner investigated nineteen consecutive patients with Gliomas. The means of rCBV and ADC values have been compared among the tumor groups with t-test and ROC curve analysis to determine threshold values of Gliomas grading. Results: Mean maximum rCBV were 2.71±1.41 for low grades (I & II), and 8.14±2.58 for high grades (III & IV) Gliomas (p=0.001). Mean minimum ADC were 1.47±.46 ×103 mm2/s for low grades (I & II), and .47±.38×103 mm2/s for high grades (III & IV) Gliomas (p=0.001). We can get 0.94×103 mm2/s for minimum ADC and 3.85 for maximum rCBV as a difference cutoff point between low and high-grade Gliomas. Conclusion: Combination of both DWI and PWI techniques, with measurement of minimum ADC and maximum rCBV can be used to distinguish between high grade and low-grade Glioma tumors.