Shear Wave Elastography for Liver Stiffness Measurement in Clinical Sonographic Examinations

Abstract

Objectives The purpose of this study was to determine the optimal minimum number of liver stiffness measurements on shear wave elastography (SWE) and to evaluate the frequency of technical failures and unreliable stiffness measurements and the intraobserver reproducibility of SWE. Methods This retrospective study was approved by our Institutional Review Board, and informed consent was waived. From August 2011 to January 2013, 540 patients underwent abdominal sonography, including SWE. In 86 patients (group 1), the minimum number of examinations was determined by comparing the intraclass correlation coefficient (ICC) of subsets of the first 2 to 14 measurements with that from 15 measurements. In 454 patients (group 2), 2 SWE sessions were performed in the right lobe within 1 day. Technical failure was defined as when no or little signal was obtained in the elastogram during the first 5 acquisitions; unreliable SWE results were defined as when the interquartile range/median liver stiffness value exceeded 30%. Intraobserver reproducibility was assessed using ICCs and Bland‐Altman plots. Results In group 1, the ICCs did not significantly increase after the first 6 measurements. In group 2, there were technical failures and unreliable results in 47 patients (10.35%) and 74 patients (16.29%), respectively. In 407 patients, after excluding technical failures, there was no significant difference in the median liver stiffness values between the 2 sessions (6.95 versus 6.86 kPa; P > .05). The overall intraobserver reproducibility was excellent (ICC, 0.95). Conclusions In this study, the optimal minimum number of SWE measurements was 6, and SWE using 6 measurements showed excellent intraobserver reproducibility.

Analyzing the Impact of Increasing Mechanical Index and Energy Deposition on Shear Wave Speed Reconstruction in Human Liver

“…This is consistent with previous studies (Yoon et al, 2014; Poynard et al, 2013). High liver capsule depth means that the ultrasound waves have to travel through more intervening tissue to reach the liver, leading to more pre-liver attenuation and thus smaller applied force.…”

“…Recently, Shear Wave Elasticity Imaging (SWEI) (Sarvazyan et al, 1998), has found success in the staging of liver fibrosis (Palmeri et al, 2011, 2008: Lazebnik, 2008; Piscaglia et al, 2011; Friedrich-Rust et al, 2009; Haque et al, 2010; Horster et al, 2010; Lupsor et al, 2009; Fierbinteanu-Braticevici et al, 2009). However, studies routinely report depth penetration limitations and exclude patients with livers and hepatic lesions deeper than 6–8 cm (Park et al, 2013), and technical failure and unreliable measurement rates for liver stiffness have been reported to increase both with elevated patient BMI (a measure of obesity) (Yoon et al, 2014), and in the presence of significant hepatic fibrosis (Poynard et al, 2013). These challenges likely result from: (1) significant propagation distances of ultrasound waves through subcutaneous fat in patients with higher BMIs, which can attenuate acoustic radiation force impulse (ARFI) excitations and abberate tracking ultrasound beams, and (2) smaller displacement amplitudes in stiffer livers.…”

Quantitative assessment of rotator cuff muscle elasticity: Reliability and feasibility of shear wave elastography

“…The reliability and validity of elastographic measurements have been investigated in several studies (Park et al, 2014, Yoon et al, 2014). Regarding the muscular tissues, in particular, the crural and the brachial muscles have been shown to have good measurement reliably with satisfactory ICCs (Brandenburg et al, 2015, Koo et al, 2013, Koo et al, 2014, Taniguchi et al, 2015).…”

“…The technique is fast, convenient and applicable to a variety of clinical scenarios in which other approaches would potentially be inadequate. To date, it has been used successfully for breast cancers diagnosis (Athanasiou et al, 2010, Park et al, 2014) and liver fibrosis staging (Ferraioli et al, 2014, Yoon et al, 2014). In addition, quantitative assessments of material properties of muscles have also been investigated by in vivo and in vitro studies (Akagi and Kusama, 2015, Hirata et al, 2015, Hug et al, 2013, Miyamoto et al, 2015, Itoigawa et al, 2015, Koo et al, 2014, Akagi et al, 2012).…”

Prediction of liver cirrhosis, using diagnostic imaging tools

“…This is expected to overcome the limitations of transient elastography, where liver stiffness cannot be measured accurately in patients with severe obesity, and ascites. Some articles have shown growing evidence for the accuracy of US elastography [33][34][35][36][37] (Table 1). Although the low reproducibility of measurements derived from operator-dependent performance remains a significant limitation of US elastography, this technique is a useful diagnostic tool for hepatic fibrosis and further validation is warranted.…”