Shear-wave ultrasound elastography of the liver in normal-weight and obese children

Abstract

Background The identification and subsequent management of liver diseases in children is challenging due to the lack of non-invasive imaging biomarkers. Ultrasound shear-wave elastography (US-SWE) is an emerging imaging technique which can quantitatively assess liver stiffness and may be useful as a tool in the management of liver disease in overweight and obese children. Purpose To evaluate US-SWE velocities of the liver in normal-weight and obese children, to correlate US-SWE findings with age and body-mass-index (BMI), and to compare US-SWE values with qualitative assessment (i.e. normal versus abnormal echogenicity) of the liver by conventional US. Material and Methods A cohort of 300 children (mean age, 9.9 ± 5.3 years; age range, 0.06-18.9 years) were studied, comprising 176 normal-weight and 124 obese participants. In each patient, both US-SWE and conventional US of the liver were obtained. Three pediatric radiologists individually and in consensus determined whether liver parenchyma was of normal or abnormal echogenicity. Results US-SWE velocities differed between normal-weight and obese children (1.08 ± 0.14 versus 1.44 ± 0.39 m/s; P < 0.001), but not by gender. Multivariate linear regression demonstrated US-SWE velocity to be primarily associated with age in normal-weight children ( P < 0.05) and with BMI in obese children ( P < 0.001). In the obese group, mean US-SWE velocity was statistically higher in participants with abnormal echogenic livers than in those with normal-appearing livers (1.53 ± 0.38 vs. 1.17 ± 0.27). The difference was not significant in the normal-weight group. Conclusion US-SWE provides a useful quantitative imaging biomarker for evaluating liver stiffness in children.

Accuracy of real-time shear wave elastography in staging hepatic fibrosis: a meta-analysis

“…Studies showed that it has excellent intraobserver and interobserver error, intraclass correlation coeffiients in three different sections of the liver ranged from 0.86 to 0.98, and the 95% confidence interval ranged from 0.71 to 0.99, suggesting the technique is highly reproducible [23,26]. An non-invasive procedure, it is very suitable for detecting therapeutic outcome after operations, such as liver transplantation [33] and can be used for screening and subsequent management of liver diseases, particularly for children [34]. Other advantages of this method include determining therapeutic response, and monitoring age-related changes, including sarcopenia and clinical frailty syndrome.…”

Shear‐wave elastography of the liver in a healthy pediatric population

“…TE has some limitations in young children; some authors reported technical failure in 17% of children younger than 2 years old, and others reported technical failure in 10% of children of any age . SWE is a noninvasive imaging technique that shows promising reliability and clinical utility for the quantitative assessment of liver tissue stiffness, particularly in children . While numerous studies have been conducted on SWE measurement of healthy adult livers, few studies have evaluated SWE in children, especially in school‐age children.…”

General advice in ultrasound based elastography of pediatric patients

“…In the obese group, mean shear wave velocity was statistically higher in children with abnormal echogenic livers than in those with normal-appearing livers (1.53 ± 0.38 vs 1.17 ± 0.27). The difference was not significant in the normal-weight group [50].…”

“…There was no statistical difference between measurements taken at different ages [51,52]. Conversely, in another study pSWE speed was primarily associated with age, BMI, but not with gender [50]. Other important factors are the transducer's frequency and the operator experience [53][54][55][56][57].…”