IMG-77. Noninvasive assessment of different gliomas and IDH status using Intravoxel Incoherent Motion Imaging

PURPOSE To assess the diagnostic performance of intravoxel incoherent motion (IVIM) MR imaging in differentiating types of gliomas and its utility in differentiating isocitrate dehydrogenase (IDH) mutant versus wild gliomas. METHOD On a 1.5T MRI scanner, 32 patients with diffuse gliomas (mean age 45.1 years; 20 males, 12 females) were examined using IVIM imaging and 15 different b-values. Perfusion fraction (f), true diffusion coefficient (D), and pseudo-diffusion coefficient (D*) were calculated using a bi-exponential model. Two b-values (0 and 1000 s/mm2) were used to compute the apparent diffusion coefficient (ADC). Relative cerebral blood volume (rCBV) measurements were obtained using the Dynamic Susceptibility Contrast (DSC) method. RESULTS Based on data from 32 patients, IVIM parameters demonstrated significant diagnostic utility. Notably, perfusion fraction (f) and diffusion coefficient (D) showed high sensitivity (94.1%). D* parameter of our study, which measures the degree of neovascularization, revealed substantial variability and was therefore less accurate in differentiating grades of glioma. D* had sensitivity and specificity of 64.7% and 80% respectively. CONCLUSION IVIM imaging shows promising results in distinguishing types of gliomas and between IDH mutant and wild-type gliomas.