title: Reproducibility of real-time shear wave elastography in the evaluation of liver elasticity.
abstract: OBJECTIVE
  To evaluate the reproducibility of real-time shear wave elastography in assessing liver elasticity in healthy volunteers.
  
  
  METHODS
  Forty-two volunteers were studied in day 1. Shear wave elastography studies were performed by using the ultrasound system Aixplorer™ (SuperSonic Imagine S.A., Aix-en-Provence, France) with a convex broadband probe. Measurements were carried by two operators, an expert (operator 1) and a novice (operator 2). Examinations were performed on the right lobe of the liver. Each operator performed 10 consecutive measurements in each volunteer. In a subset of volunteers (n=18) measurements were performed twice on two different days (day 1 and day 2). Intraobserver and interobserver agreement were assessed by intraclass correlation coefficient.
  
  
  RESULTS
  Intraobserver agreement between measurements performed in the same subject in the same day (day 1 or day 2) showed intraclass correlation coefficient values of 0.95 (95% confidence interval, 0.93-0.98) and 0.93 (95% confidence interval, 0.90-0.96) for operator 1 and operator 2, respectively. Intraobserver agreement between measurements performed in the same subject in different days showed intraclass correlation coefficient values of 0.84 (95% confidence interval, 0.69-0.98) and 0.65 (95% confidence interval, 0.39-0.91) for operator 1 and operator 2, respectively. Interobserver agreement was 0.88 (95% confidence interval, 0.82-0.94).
  
  
  CONCLUSIONS
  The results of this study show that shear wave elastography is a reliable and reproducible noninvasive method for the assessment of liver elasticity. Expert operator had higher reproducibility of measurements over time than novice operator.
authors: Ultrasound Unit, Infectious Diseases Department, IRCCS San Matteo Hospital Foundation, University of Pavia, Via Taramelli 5, 27100 Pavia, Italy. giovanna.ferraioli@unipv.it
authors: Giovanna
authors: G
authors: Ferraioli
authors: Carmine
authors: C
authors: Tinelli
authors: Mabel
authors: M
authors: Zicchetti
authors: Elisabetta
authors: E
authors: Above
authors: Gianluigi
authors: G
authors: Poma
authors: Marta
authors: M
authors: Di Gregorio
authors: Carlo
authors: C
authors: Filice
mesh_terms: D000328:Adult; D000465:Algorithms; D003199:Computer Systems; D055119:Elastic Modulus / Q000502:physiology; D054459:Elasticity Imaging Techniques / Q000379:methods*; D005260:Female; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D008099:Liver / Q000000981:diagnostic imaging* / Q000502:physiology*; D008875:Middle Aged; D015588:Observer Variation; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D055815:Young Adult