Table 1.
Benefits and Limitations of different modalities used in estimation of skeletal muscle mass
| Modality | Benefits | Limitations |
|---|---|---|
| MRI | • No ionising radiation | • Expensive |
| • Good for imaging soft tissues | • Time consuming | |
| • Able to review images after scanning | • Limited accessibility for frail community based patients and those with cognitive impairment | |
| • Thorough image acquisition | • Confined space in scanner | |
| • Limited availability | ||
| • Cannot use if patient has metal work/some pacemakers | ||
| • Requires interpretation by radiologist | ||
| CT | • Able to review images after scanning | • Expensive |
| • Thorough image acquisition | • Radiation exposure | |
| • Time consuming | ||
| • Poor accessibility | ||
| • Confined space in scanner | ||
| • Limited availability | ||
| • Requires interpretation by radiologist | ||
| DXA | • Can also identify bone mineral density | • Expensive |
| • Radiation exposure is small | • Radiation exposure | |
| • Time consuming | ||
| • Poor accessibility | ||
| BIA | • Safe | |
| No radiation exposure | • Dependent on hydration status | |
| • Quick to perform | • No assessment of reliability in dependent oedema, congestive cardiac failure and renal failure | |
| • No reliability data in frail older adults | ||
| • Not universally portable | ||
| • Cannot use if patient has metal work or electronic device implants | ||
| • Varying accuracy between machines | ||
| Ultrasound | • Extremely safe | • Variety of probes required to achieve varying depth/resolution |
| • No ionising radiation | • Limited use in obese patients | |
| • Ability to perform dynamic testing | • Quality and interpretation of images is user dependent | |
| • Portable | • No criteria for diagnosis of low muscle mass | |
| • Cost-effective | ||
| • Low-risk | ||
| • Quick to perform | ||
| • Suitable in all patient groups | ||
| • Can be interpreted at bedside by a lay sonographer | ||