Magnetic Resonance Imaging Biomarkers of Muscle

Area of Science:

• Biomedical Imaging
• Musculoskeletal Radiology
• Quantitative MRI

Background:

• Skeletal muscle assessment is crucial for diagnosing and managing various neuromuscular disorders.
• Quantitative MRI (qMRI) offers objective, reproducible measures of muscle tissue properties.
• Established MRI techniques lack the specificity to fully characterize muscle pathophysiology.

Purpose of the Study:

• To provide a comprehensive overview of current quantitative MRI techniques for skeletal muscle.
• To discuss the physiological underpinnings and analytical approaches for various qMRI parameters.
• To summarize the clinical utility of qMRI in the context of muscle diseases.

Main Methods:

• Review of established and emerging qMRI techniques including parametric mapping (T1, proton density fat fraction, T2, diffusion tensor imaging).
• Inclusion of advanced methods such as magnetization transfer and strain mapping.
• Discussion of image processing, analysis, and application in normal subjects.

Main Results:

• Detailed explanation of qMRI parameters, their relation to muscle physiology/pathophysiology, and imaging sequences.
• Coverage of techniques from morphometrics and fat fraction to diffusion and macromolecular fraction.
• Demonstration of qMRI's utility across a spectrum of muscle disease states.

Conclusions:

• Quantitative MRI provides valuable insights into skeletal muscle structure and function.
• qMRI techniques are increasingly vital for accurate diagnosis and monitoring of muscle pathologies.
• Further research and standardization of qMRI protocols will enhance its clinical impact.