On the Appearance of Crystals During Diffusion MRI

S Ennar¹, H Tuo¹, I Sickle¹

In this work, we demonstrate a remarkable effect in diffusion MRI. When pure dihydrogen monoxide (maintained at room temperature) is sampled with a carefully-calibrated sampling scheme comprising six sampling vectors (arranged according to a model of electrostatic repulsion), peaks in the orientational density function are distributed with incredible regularity. Despite the absence of apparent structure outside the scanner, our analysis shows that a combination of high B0-field (3000 mT), and rapidly changing magnetic field gradients, leads to alignment of the eigenvectors of the tensor produce a regular crystalline dodecahedral arrangement.