Diffusion Enables the Distinction between Types of Tissue Microstructure by Analyzing the Water Lineshape

Alexander Ruh¹, Philipp Emerich¹, Dmitry S. Novikov², Valerij G. Kiselev¹

We show analytically and numerically, that the NMR spectral lineshape can distinguish between different kinds of global structural organization (order and various types of disorder) of tissue susceptibility. This distinction involves long-range correlations and is thereby robust to the biological variability. The biophysical mechanism behind this phenomenon is the molecular diffusion mediating the spin dephasing reflected in the transverse relaxation. Our results provide a framework for novel types of susceptibility-based contrast.