MODL-39. CHARACTERIZING NON-ENHANCING TUMOR USING MULTI-SHELL DIFFUSION MRI

Abstract Characterizing infiltration in the non-enhancing tumor (NET) is clinically crucial as leads to progression, and a reduction survival times. As voxel-wise biopsy of these regions infeasible, non-invasive MRI-based identification would be significant contribution. Diffusion MRI (dMRI), with its ability model different levels water restriction, caused by edema, well positioned NET. This achieved via multicomparment modeling (MCM) dMRI where infiltration, vasogenic edema healthy tissue (with complex fibers) form compartments. Current MCM approaches are either not designed for NET or rely on advanced scans currently feasible clinic. The simplest ball-tensor models, including Hoy 2014 using multi-shell data FERNET 2020 single-shell data, consists free compartment that models tensor underlying tissue. These single-tensor methods cannot WM fibers. Our proposed two steps. First, bundles fit: an isotropic bundle balls diffusivity restricted diffusivity, containing stick zeppelin, corresponding intra-cellular extra-cellular diffusion axons, respectively. Next, fiber orientation distribution (FOD) estimated from fitted parameters. We applied our eight patients glioblastoma, one patient metastatic brain tumor. method produces maps (CSF), diffusion, intra-cellular, volume fractions. Preliminary results show map comprises 46% compare 15% infiltrated GBM edema. In conclusion, we demonstrate shows promise characterize region various tumors, distinguishing types. compartments will provide invaluable radiomic features no other modality can capture.