Background field inhomogeneity effects on hyperpolarized 129Xe diffusion-weighted MRI at 1.5T and 3T

Background field inhomogeneities due to air-tissue interface magnetic susceptibility differences in the lungs increases derived ADC measurements from ³He PGSE diffusion-weighted (DW) lung MRI at higher field strengths. To determine if the same effects are observed with ¹²⁹Xe DW-MRI, ¹²⁹Xe ADC and mean diffusive length scale (Lm_D) from healthy volunteers imaged at 1.5T and 3T were compared. A small bias towards increased ¹²⁹Xe ADC (6.3%) and Lm_D (2.2%) values at 3T was obtained, which is smaller than the reported bias of ³He ADC (15.5%) and ³He mean chord length (10.5%), and similar to the reported ¹²⁹Xe DW-MRI inter-scan repeatability differences.