2D shear wave elastography for the assessment of quadriceps entheses-a methodological study

Defining normal enthesis stiffness range in a healthy adult population

OBJECTIVES

This study explores the correlation between volunteer demographics with enthesis stiffness and intra- and interobserver agreements using shear wave elastography (SWE).

METHODS

Ninety-eight healthy volunteers were recruited. SWE was performed on quadriceps, suprapatellar, infrapatellar, and Achilles entheses. The stiffness measurements were measured in shear wave velocity (SWV).

RESULTS

Mann-Whitney test revealed insignificant difference in SWV among gender. Wilcoxon signed-rank test showed significant difference in SWV between left and right Achilles entheses. Spearman correlation test revealed moderate negative correlation between SWV and age group in quadriceps (ρ, -0.45, P < .01), and weak negative correlation in suprapatellar (ρ, -0.31, P < .01), and left Achilles (ρ, -0.29, P < .01). Multiple linear regression analysis showed subjects' demographic significantly predicted quadriceps, suprapatellar, and left Achilles entheses stiffness with only age statistically significantly to the prediction (P < .05). Kruskal-Wallis showed significant differences in SWV for quadriceps (P = .01), suprapatellar (P = .03), and left Achilles (P = .01) among different age groups. Good interobserver [0.79-0.86 (95% CI, 0.32-0.94)] and interobserver agreement [0.78-0.89 (95% CI, 0.62-0.95)] were found in all the entheses.

CONCLUSION

SWE emerges as a reproducible method for entheses stiffness quantification, with the study highlighting age as a significant factor impacting SWV in quadriceps, suprapatellar, and left Achilles entheses. Among the studied entheses, SWV for Achilles enthesis is the highest in all age groups.

ADVANCES IN KNOWLEDGE

The study significantly contributes to the understanding of enthesis stiffness by exploring the influence of gender, BMI, and age.

Shear wave elastography in chronic kidney disease - the physics and clinical application

Chronic kidney disease is a leading public health problem worldwide. The global prevalence of chronic kidney disease is nearly five hundred million people, with almost one million deaths worldwide. Estimated glomerular filtration rate, imaging such as conventional ultrasound, and histopathological findings are necessary as each technique provides specific information which, when taken together, may help to detect and arrest the development of chronic kidney disease, besides managing its adverse outcomes. However, estimated glomerular filtration rate measurements are hampered by substantial error margins while conventional ultrasound involves subjective assessment. Although histopathological assessment is the best tool for evaluating the severity of the renal pathology, it may lead to renal insufficiency and haemorrhage if complications occurred. Ultrasound shear wave elastography, an emerging imaging that quantifies tissue stiffness non-invasively has gained interest recently. This method applies acoustic force pulses to generate shear wave within the tissue that propagate perpendicular to the main ultrasound beam. By measuring the speed of shear wave propagation, the tissue stiffness is estimated. This paper reviews the literature and presents our combined experience and knowledge in renal shear wave elastography research. It discusses and highlights the confounding factors on shear wave elastography, current and future possibilities in ultrasound renal imaging and is not limited to new sophisticated techniques.