Automatic assessment of shear wave elastography quality and measurement reliability in the liver

A strategy is proposed that accesses the quality of individual shear wave elastography (SWE) exams and the reliability of elasticity measurements in clinical practice. For that purpose, a confidence index based on temporal stability and SWE filling was defined to provide an automatic estimation of each scan quality: high (HG) or low (LG) grade. With this index, the intra-observer acquisition variability assessed by comparing consecutive scans of the same patient was 17% and 32% for HG and LG clips, respectively. The measurement quantification variability assessed by comparing the measurements of a radiologist with those of a trained operator and of two automatic measurements on a same clip averaged 13% and 22% for HG and LG exams, respectively. It was found that SWE measurements depend greatly on the quality of the acquired data. The proposed quality index (HG or LG) provides objective input on the accuracy and diagnostic reliability of SWE measurements.