The Concept of CMR
Slides, videos and moreEvaluating CMR
Imaging Techniques
Magnetic Resonance Imaging (MRI)
- 1Key Points (1 page)
- 2Imaging Techniques (1 page)
- 3Magnetic Resonance Imaging: How it Works (1 page)
- 4Determining Tissue Area or Mass (1 page)
- 5Measuring Skeletal Muscle Mass (1 page)
- 6Measuring Intra-abdominal Fat (1 page)
- 7Measuring Ectopic Fat Using MRI (1 page)
- 8References (1 page)
Measuring Skeletal Muscle Mass
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Figure 2: 
Figure 2: MRI and CT are the gold standard measures for in vivo quantification of skeletal muscle mass (Figure 2). Muscle mass and changes to it are related to muscle strength (12-14), and accurately determining skeletal muscle mass is particularly important in elderly populations who are at increased risk of sarcopenia and functional impairment due to low muscle mass. Measures of skeletal muscle by a single MRI image have been validated using cadaver measures and show a high level of agreement (R2=0.94, standard error of estimate=10%) and a low coefficient of variation (CV~2%) (15). Compared to cadaver values, MRI error improved to approximately 1% when volume measures were acquired using multiple images. However, as this is a very time-consuming and expensive process, a single image at the mid-thigh is commonly used as a proxy measure of whole body skeletal muscle in both men and women (R2=0.77-0.79) (16).
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