  Purpose: B1+ and T1 corrections and dynamic multi-coil shimming approaches
were proposed to improve the fidelity of high isotropic resolution Generalized
slice dithered enhanced resolution (gSlider) diffusion imaging. Methods: An
extended reconstruction incorporating B1+ inhomogeneity and T1 recovery
information was developed to mitigate slab-boundary artifacts in short-TR
gSlider acquisitions. Slab-by-slab dynamic B0 shimming using a multi-coil
integrated {\Delta}B0/Rx shim-array, and high in-plane acceleration
(Rinplane=4) achieved with virtual-coil GRAPPA were also incorporated into a 1
mm isotropic resolution gSlider acquisition/reconstruction framework to achieve
an 8-11 fold reduction in geometric distortion compared to single-shot EPI.
Results: The slab-boundary artifacts were alleviated by the proposed B1+ and T1
corrections compared to the standard gSlider reconstruction pipeline for
short-TR acquisitions. Dynamic shimming provided >50% reduction in geometric
distortion compared to conventional global 2nd order shimming. 1 mm isotropic
resolution diffusion data show that the typically problematic temporal and
frontal lobes of the brain can be imaged with high geometric fidelity using
dynamic shimming. Conclusions: The proposed B1+ and T1 corrections and
local-field control substantially improved the fidelity of high isotropic
resolution diffusion imaging, with reduced slab-boundary artifacts and
geometric distortion compared to conventional gSlider acquisition and
reconstruction. This enabled high-fidelity whole-brain 1 mm isotropic diffusion
imaging with 64 diffusion-directions in 20 minutes using a 3T clinical scanner.
