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.