Reproducibility of 2‐Dimensional Shear Wave Elastography Assessment of the Liver: A Direct Comparison With Point Shear Wave Elastography in Healthy Volunteers

• Published in: Journal of ultrasound in medicine Vol. 36; no. 8; pp. 1563 - 1569
• Main Authors: Fang, Cheng, Konstantatou, Eleni, Romanos, Odyssefs, Yusuf, Gibran T., Quinlan, Daniel J., Sidhu, Paul S.
• Format: Journal Article
• Language: English
• Published: England 01.08.2017
• Subjects: acoustic radiation force impulse imaging; Adult; ARFI; Elasticity Imaging Techniques - methods; Female; Humans; Liver - anatomy & histology; Male; Observer Variation; Reference Values; reproducibility; Reproducibility of Results; shear wave elastography; ultrasound; ARFI; acoustic radiation force impulse imaging; reproducibility; ultrasound; shear wave elastography
• ISSN: 0278-4297; 1550-9613
• DOI: 10.7863/ultra.16.07018

Objectives Two‐dimensional shear wave elastography (2D‐SWE) imaging for the noninvasive assessment of tissue stiffness was assessed for reproducibility in healthy volunteers in quantifying liver elasticity, compared with an established point shear wave elastography (p‐SWE) technique also known as virtual touch quantification (VTQ) (SIEMENS). Methods Eleven healthy volunteers were examined by four experienced operators on two occasions, separated by two weeks (sessions A and B). Ten 2D‐SWE using LOGIQ E9 and p‐SWE measurements using VTQ (in meters per second) were consecutively taken from deep portions of liver segments 5 or 6 away from vascular structures, using standard techniques. Inter‐ and intra‐observer agreement was assessed by intraclass coefficient (ICC). Results A total of 880 2D‐SWE and p‐SWE velocities were recorded. Mean values from the four operators ranged between 1.188 and 1.196 m/s for 2D‐SWE and 1.170 to 1.207 m/s for p‐SWE. Interobserver reproducibility was good for both sessions with ICCs of 0.88 and 0.93 (2D‐SWE) and 0.87 and 0.93 (p‐SWE). The overall intra‐operator reproducibility between sessions A and B was good for both p‐SWE and 2D‐SWE with ICC of 0.87 and 0.83, respectively. For inter‐ and intra‐observer variability, the ICC was more than or equal to 0.71, indicating that the results were reliable. There was a strong and significant correlation between the 2D‐SWE and p‐SWE measurements (r = 0.87, P = .0006), but their velocities did not agree equally across different velocities. Conclusions Two‐dimensional SWE using LOGIQ E9 is a reliable and reproducible method for measuring elasticity in healthy volunteers and has a similar degree of reliability as p‐SWE using VTQ, but absolute measurements from the two techniques should not be used interchangeably.