Dynamic magnetic resonance imaging of muscle contraction in facioscapulohumeral muscular dystrophy

ABSTRACT Background Quantitative muscle MRI (water-T2 and fat mapping) is being increasingly used to assess disease involvement in muscle disorders, while imaging techniques for assessment of the dynamic and elastic muscle properties have not been translated yet into clinics. Methods Here, we quantitatively characterized muscle deformation (strain) in patients affected by facioscapulohumeral muscular dystrophy (FSHD), a prevalent muscular dystrophy, by applying dynamic MRI synchronized with neuromuscular electrical stimulation (NMES). We evaluated the quadriceps muscles in 34 ambulatory patients and 12 healthy controls, at 6 month intervals. Results We found that while a subgroup of patients behaved similarly to controls, for another subgroup the strain significantly decreased over time (50% over 1.5 years). Dynamic MRI parameters did not correlate with quantitative MRI. Conclusions In conclusion, our results suggest that the evaluation of muscle ability to contract by NMES-MRI could be used to explore the elastic properties and monitor muscle involvement in FSHD and other neuromuscular disorders.