Clinical Research with Advanced Diffusion Encoding Methods in MRI

This chapter offers a comprehensive summary of applications of advanced diffusion encoding methods in MRI within a narrowly defined area of in vivo human measurements with imaging read-out and voxel-by-voxel data analysis. The list of methods comprises tensor-valued encoding to investigate cell densities, shapes, and orientations in heterogeneous tissues, time/frequency-dependent encoding for estimating structural length scales, adjustable velocity-encoding to monitor flow in the microcapillary network, double encoding with varying mixing times to assess diffusional exchange between distinct tissue microenvironments and across cell membranes, and relaxation-diffusion correlation to resolve and separately characterize tissue microenvironments in terms of their local chemical composition and microstructure. The shown examples include proof-of-concept measurements on healthy volunteers, pilot investigations of pathologies, and clinical research involving 10-100 subjects. Studied organs include brain, breast, prostate, liver, kidney, placenta, muscle, and peripheral nerve, with examples of pathologies from tumors, schizophrenia, multiple sclerosis, stroke, neurocysticercosis, pre-eclampsia, and chronic exertional compartment syndrome