Resolving complex white matter architecture in the human brain at 64 mT

Motivation: Facilitating white matter mapping in traditionally inaccessible low income settings. Goal(s): Demonstration of a viable protocol to resolve complex white matter architecture at low field. Approach: A multi-modality protocol was devised to allow feasible acquisition of multi-direction diffusion weighted imaging (DWI) datasets at 64mT. A modified DWI protocol is shown, employing voxel-wise encoding non-uniformity calibration, extended readout, and optimal sampling density. Machine learning based denoising was employed to significantly reduce scan duration. T1 weighted scans were super-resolved to guide tractography. Results: Anatomically-constrained tractography was shown to be viable at low field, and fine white matter microstructure was successfully recovered. Impact: This work demonstrates that a 64mT system is capable of resolving microstructural detail even with lowered SNR, and gradient nonuniformity. This may have relevance in studies examining white matter neurodevelopment in historically underrepresented populations in low-income settings.