Is there a place for ultrasound in diagnosing sarcopenia?

Abstract

Sarcopenia is a progressive and generalised skeletal muscle disorder which presents as loss of muscle mass and function and is associated with increased likelihood of adverse outcomes, reduced quality of life and increased mortality. In developed countries, the prevalence of sarcopenia is rising due to increasing life expectancy. Still, in many clinical settings, sarcopenia may be overlooked and undertreated. While several tools are available for assessment of muscle mass and quality, there remains a need for safe, reliable and accurate diagnostic methods which can be implemented for both sarcopenia diagnosis and the evaluation of treatment efficacy. Ultrasound is an accessible and non-ionizing imaging technique that can potentially be used for that purpose. Several ultrasound parameters have been identified for their utility to provide assessment of muscle mass, quality and/or muscle function. Ultrasound is gaining recognition as an accurate and reproducible method of muscle mass assessment. However, there are still several limitations that preclude the application of ultrasound in routine clinical practice. Implementing a harmonized measurement protocol and conducting large-scale longitudinal studies on both healthy individuals and various patient cohorts could enable the establishment of clearly defined reference values for individual ultrasound parameters and, in turn, potentially reliable differentiation between normal and sarcopenic states. This review presents a summary of current evidence regarding the utility of ultrasound muscle assessment in diagnosing sarcopenia, the agreement between ultrasound and reference methods for assessing muscle mass and muscle quality, as well as highlights areas where further research is needed.