High Spatial-Resolution DTI using 32-Channel Head Coil at Human 7 T

Ha-Kyu Jeong^1,2, John C. Gore^1,2, Adam W. Anderson^1,2

High spatial-resolution DTI at 7 T has not been commonly implemented using single-shot methods due to technical difficulties in reducing the effects of geometric distortions and/or blurring artifacts and B1-inhomogeneities that cause SNR decreases in some regions. We have previously suggested methods for diffusion-weighted multi-shot SENSE acquisitions with 2-D navigators and image-domain column-by-column reconstructions using a point spread function. With a 32 channel head coil, the B1-inhomogeneity induced regional SNR decrease can be ameliorated, and diffusion-weighted single-shot and multi-shot images show higher SNR compared with 16 channel coil data. Moreover, the suggested approach can delineate tiny white matter fiber structures at sub-millimeter resolution even in regions with relatively high B1-inhomogeneity, where conventional single-shot methods do not perform adequately.