Prentiss, Isaac E.; Hakhu, Sasha; Lingo VanGilder, Jennapher; Hareesh, Parvathy; Hooyman, Andrew; Yalim, Jason; Hines, Justin; LaFond, Gabe; Ofori, Edward; Baxter, Leslie C.; Zhou, Yuxiang; Hu, Leland S.; Schilling, Kurt G.; Beeman, Scott C. (2026).听.听Tomography, 12(6), 78.听
Swelling around聽brain tumors聽can make it difficult to identify nearby聽white matter鈥攖he bundles of nerve fibers that carry signals between different parts of the brain鈥攐n standard聽magnetic resonance imaging (MRI). This can complicate surgical planning by making it harder to determine the safest path for removing a tumor while preserving important brain connections. In this proof-of-concept study, the researchers evaluated whether advanced聽diffusion MRI聽techniques, which model how water moves through different microscopic tissue compartments, could better identify white matter in areas affected by swelling (edema). Using MRI data from five patients with聽meningiomas聽(typically benign brain tumors), they compared conventional聽diffusion tensor imaging (DTI)聽with two advanced methods:聽Neurite Orientation Dispersion and Density Imaging (NODDI)聽and the聽Standard Model (SM). The advanced techniques preserved measures of white matter organization in swollen tissue much better than standard DTI and more successfully traced white matter pathways through these regions. These findings suggest that biophysical diffusion MRI models may improve the mapping of critical white matter tracts before brain surgery, helping surgeons better plan procedures in patients with tumors surrounded by edema.
Figure 1.聽Representative (A) post-contrast T1-weighted images, (B) T2-weighted FLAIR images, (C) FA maps, (D) single-shell FW-FA maps, (E) multi-shell FW-FA maps, (F) ODI maps, and (G) P2聽maps are shown. Post-contrast T1-weighted images best reflect tumor location, and T2-weighted FLAIR images best reflect tumor plus edema location. DTI鈥檚 FA (where WM is typically represented by a brighter signal intensity) fails to identify WM tracts through regions of edema (seen as hyperintense signal traced in T2-FLAIR images), whereas NODDI鈥檚 ODI (where WM is represented by a darker signal intensity) retains WM structure irrespective of edema presence. Similarly, the SM鈥檚 P2map (where WM is typically represented by a brighter signal intensity) succeeds. Representative image planes were chosen on a per-patient basis to best reflect the lesion.