Quantitative MR in dystrophic muscle : It's more than fat

Abstract

The overall aim of this thesis was to combine various quantitative MR measurements and compare these combined measurements between Duchenne Muscular Dystrophy (DMD) patients and healthy age-matched controls both on a cross-sectional and longitudinal level, in order to generate a better understanding of the underlying pathophysiology of the disease and ideally to determine the potential of these MRI outcome parameters for monitoring muscle tissue changes in a clinical setting. In order to achieve this aim, we assessed the effect of spatial localization, data quality and confounding effects on the quantification process for various MR outcome parameters. We found that, sufficient SNR is a prerequisite for reliable MR measurements. In addition, we found that út and water T2 changes need to be monitored in DTI in skeletal muscle. Second, we used a combination of quantitative MRI and spatially resolved 31P MRS to contribute to the understanding of the pathophysiology in DMD. We found that PDE-levels and water T2 changes occurred prior to the replacement of muscle tissue by fat. Subsequently, we found that PDE-levels had the potential to function as a marker to monitor muscle tissue changes in DMD