Inter-sonographer reproducibility of quantitative ultrasound outcomes and shear wave speed measured in the right lobe of the liver in adults with known or suspected non-alcoholic fatty liver disease

Aiguo Han; Yassin Labyed; Ethan Z Sy; Andrew S Boehringer; Michael P Andre; John W Erdman Jr; Rohit Loomba; Claude B Sirlin; William D O'Brien Jr

doi:10.1007/s00330-018-5541-9

Inter-sonographer reproducibility of quantitative ultrasound outcomes and shear wave speed measured in the right lobe of the liver in adults with known or suspected non-alcoholic fatty liver disease

Eur Radiol. 2018 Dec;28(12):4992-5000. doi: 10.1007/s00330-018-5541-9. Epub 2018 Jun 4.

Authors

Aiguo Han¹, Yassin Labyed², Ethan Z Sy³, Andrew S Boehringer³, Michael P Andre^{4

5}, John W Erdman Jr⁶, Rohit Loomba⁷, Claude B Sirlin³, William D O'Brien Jr⁸

Affiliations

¹ Bioacoustics Research Laboratory, Department of Electrical and Computer Engineering, University of Illinois at Urbana-Champaign, 306 North Wright Street, Urbana, IL, 61801, USA.
² Siemens Healthineers USA, 22010 South East 51st Street, Issaquah, WA, 98029, USA.
³ Liver Imaging Group, Department of Radiology, University of California at San Diego, 9452 Medical Center Drive, La Jolla, CA, 92037, USA.
⁴ Department of Radiology, University of California at San Diego, 9500 Gilman Drive, San Diego, CA, 92093, USA.
⁵ San Diego VA Healthcare System, San Diego, CA, USA.
⁶ Department of Food Science and Human Nutrition, University of Illinois at Urbana-Champaign, 905 South Goodwin Avenue, Urbana, IL, 61801, USA.
⁷ NAFLD Research Center, Division of Gastroenterology, Department of Medicine, University of California at San Diego, 9500 Gilman Drive, La Jolla, CA, 92093, USA.
⁸ Bioacoustics Research Laboratory, Department of Electrical and Computer Engineering, University of Illinois at Urbana-Champaign, 306 North Wright Street, Urbana, IL, 61801, USA. wdo@uiuc.edu.

Abstract

Objectives: To assess inter-sonographer reproducibility of ultrasound attenuation coefficient (AC), backscatter coefficient (BSC) and shear wave speed (SWS) in adults with known/suspected non-alcoholic fatty liver disease (NAFLD).

Methods: The institutional review board approved this HIPAA-compliant prospective study; informed consent was obtained. Participants with known/suspected NAFLD were recruited and underwent same-day liver examinations with a clinical scanner. Each participant was scanned by two of the six trained sonographers. Each sonographer performed multiple data acquisitions in the right liver lobe using a lateral intercostal approach. A data acquisition was a single operator button press that recorded a B-mode image, radio-frequency data, and the SWS value. AC and BSC were calculated from the radio-frequency data using the reference phantom method. SWS was calculated automatically using product software. Intraclass correlation coefficient (ICC) and within-subject coefficient of variation (wCV) were calculated for applicable metrics.

Results: Sixty-one participants were recruited. Inter-sonographer ICC was 0.86 (95% confidence interval: 0.77-0.92) for AC and 0.87 (0.78-0.92) for log-transformed BSC (logBSC = 10log₁₀BSC) using one acquisition per sonographer. ICC was 0.88 (0.80-0.93) for both AC and logBSC averaging 5 acquisitions. ICC for SWS was 0.57 (0.29-0.74) using one acquisition per sonographer, and 0.84 (0.66-0.93) using 10 acquisitions. The wCV was ~7% for AC, and 19-43% for SWS, depending on number of acquisitions.

Conclusions: Hepatic AC, BSC and SWS measures on a clinical scanner have good inter-sonographer reproducibility in adults with known or suspected NAFLD. Multiple acquisitions are required for SWS but not AC or BSC to achieve good inter-sonographer reproducibility.

Key points: • AC, BSC and SWS measurements are reproducible in adults with NAFLD. • Inter-sonographer reproducibility of SWS measurement improves with more acquisitions being averaged. • Multiple acquisitions are required for SWS but not AC or BSC.

Keywords: Elastography; Liver fibrosis; Non-alcoholic fatty liver disease; Reproducibility of results; Ultrasonography.

MeSH terms

Adult
Analysis of Variance
Elasticity Imaging Techniques / methods
Female
Humans
Image Processing, Computer-Assisted
Liver / diagnostic imaging
Male
Middle Aged
Non-alcoholic Fatty Liver Disease / diagnostic imaging*
Observer Variation
Phantoms, Imaging
Prospective Studies
Reproducibility of Results
Software
Ultrasonography / standards*

Abstract

MeSH terms

Grants and funding