Whole-Brain, High-Resolution Diffusion-Weighted MRSI with Improved Phase Correction

Motivation: In vivo DW-MRSI, although a potentially powerful microstructural imaging tool, can suffer from poor resolutions, long acquisition times and motion-induced phase errors. Goal(s): Whole-brain, high-resolution, DW-MRSI within clinically relevant time. Approach: A fast multi-slab acquisition with 3D phase navigators and flow-compensated diffusion gradients was developed. Processing strategies integrated spatially varying phase correction and subspace-based reconstruction and quantification. Results: Phantom and in vivo experiments with validation against a single-voxel technique demonstrated strong qualitative and quantitative performances, e.g., whole-brain metabolite ADC mapping at a 5.2×5.2×5.0 mm3 resolution in around 20mins. Impact: The proposed method advanced capability of in vivo DW-MRSI and may facilitate compartment/cell-type-specific tissue microstructural investigations.