Multisample Ultrasound Point Shear Wave Elastography of the Liver: Repeatability and Agreement With Conventional Point Shear Wave Elastography.

Abstract

To characterize the technical performance of a multisample ultrasound point shear wave elastography (pSWE) technique that allows 15 individual measurements of liver stiffness in a single acquisition. In 56 overweight and obese adults, research ultrasound examinations were performed using conventional pSWE and multisample pSWE (Sequoia; Siemens Healthineers). Five independent measurements were acquired with the conventional technique over five consecutive breath holds (5C1 and DAX transducers). A single multisample acquisition (DAX transducer) of up to 15 unique measurements was acquired during a single breath hold. All imaging was performed before (baseline) and after a "coffee break" (repeat). Median liver stiffness measurements between techniques and between baseline and repeat imaging were compared using Pearson correlation (r) and intra-class correlation (ICC) coefficients. Mean participant age was 33.7 ± 11.4 years; 40 participants were female. There was high correlation between conventional pSWE measurements obtained using the 5C1 and DAX transducers at baseline (r = .75 [95% CI: 0.61-0.85], P < .0001) and repeat (r = .88 [95% CI: 0.78-0.92], P < .0001). There was moderate agreement between conventional pSWE measurements obtained using the 5C1 and DAX transducers at baseline (ICC = 0.69 [95% CI: 0.52-0.81]), and good agreement at repeat (ICC = 0.81 [95% CI: 0.65-0.90]). There was moderate correlation (r = .59 [95% CI: 0.39-0.74], P < .0001) and moderate agreement (ICC = 0.58 [95% CI: 0.38-0.73]) between baseline conventional and multisample pSWE measurements acquired using the DAX transducer; there was high correlation (r = .73 [95% CI: 0.57-0.83], P < .0001) and moderate agreement (ICC = 0.72 [95% CI: 0.56-0.82] between techniques at repeat. There was moderate correlation (r = .65 [95% CI: 0.46-0.78], P < .0001) and moderate agreement (ICC = 0.64 [95% CI: 0.45-0.77]) between baseline and repeat multisample pSWE measurements. Multisample pSWE, allowing up to 15 measurements in a single breath hold, showed moderate to high correlation and moderate agreement with conventional pSWE.