Quantitative whole-body MRI in FSHD: assessing systemic involvement and future directions

Area of Science:

• Neurology
• Biomedical Imaging
• Musculoskeletal Disorders

Background:

• Facioscapulohumeral muscular dystrophy (FSHD) is a progressive neuromuscular disorder characterized by variable, asymmetric muscle degeneration.
• Early assessments of FSHD relied on qualitative MRI ratings or limited muscle sampling, hindering precise tracking of disease progression.

Purpose of the Study:

• To review ten key lessons from the evolution of MRI techniques in FSHD research.
• To highlight the benefits of quantitative whole-body MRI (WBMRI) using Dixon methods for detailed muscle analysis in FSHD.

Main Methods:

• Focus on quantitative whole-body MRI (WBMRI) employing chemical-shift-based water-fat-separation imaging (Dixon) two-echo methods.
• Inclusion of short tau inversion recovery (STIR) imaging and other quantitative biomarkers for comprehensive context.
• Comparison of WBMRI Dixon methods with earlier qualitative and sparse sampling approaches.

Main Results:

• WBMRI with Dixon methods allows for muscle-by-muscle quantification across the entire body, revealing novel metrics.
• Quantitative MRI data provides a more sensitive way to monitor muscle and functional task progression in FSHD.
• Current functional endpoints can obscure disease changes due to confounding factors like geometry and compensation.

Conclusions:

• Muscle-informed, patient-specific clinical trial designs are crucial for improving sensitivity and statistical power.
• Future research should integrate WBMRI with motion capture, biomechanics, and complementary biomarkers for deeper FSHD understanding.
• Advancements in quantitative MRI offer a path to better comprehend FSHD expression, progression, and functional impact.