Muscle Diffusion tensor imaging shows changes in non-fat infiltrated muscles in late-onset Pompe disease (LOPD)

Quantitative MRI-markers are essential for monitoring disease progression in late-onset pompe disease (LOPD). Using muscle diffusion tensor imaging (mDTI) and mDixon we evaluated differences in diffusion parameters in six thigh and seven calf muscles - with <10% and >10% fat-fraction - of 18 LOPD and 29 healthy controls (HC). Upper leg muscles with <10% fat-fraction showed significant differences in MD, RD, λ_1-3 and MD positively correlated with 6-MWT (p=0.003). mDTI reveals an increased diffusion restriction in muscles of LOPD-patients with and without fat-infiltration and could reflect structural changes prior to fatty degeneration.