The World Federation for Ultrasound in Medicine and Biology (WFUMB) endorsed the development of this document on multiparametric ultrasound. Part 1 is an update to the WFUMB Liver Elastography Guidelines Update released in 2018 and provides new evidence on the role of ultrasound elastography in chronic liver disease. The recommendations in this update were made and graded using the Oxford classification, including level of evidence (LoE), grade of recommendation (GoR) and proportion of agreement (Oxford Centre for Evidence-Based Medicine [OCEBM] 2009). The guidelines are clinically oriented, and the role of shear wave elastography in both fibrosis staging and prognostication in different etiologies of liver disease is discussed, highlighting advantages and limitations. A comprehensive section is devoted to the assessment of portal hypertension, with specific recommendations for the interpretation of liver and spleen stiffness measurements in this setting.

The Ultrasound Physician Branch of the Chinese Medical Doctor Association sought to develop evidence-based recommendations on the operational standards for 2-D shear wave elastography examination of musculoskeletal tissues. A consensus panel of 22 Chinese musculoskeletal ultrasound experts reviewed current scientific evidence and proposed a set of 12 recommendations for 13 key issues, including instruments, operating methods, influencing factors and image interpretation. A final consensus was reached through discussion and voting. On the basis of research evidence and expert opinions, the strength of recommendation for each proposition was assessed using a visual analog scale, while further emphasizing the best available evidence during the question-and-answer session. These expert consensus guidelines encourage facilitation of the standardization of clinical practices for collecting and reporting shear wave elastography data.

UNASSIGNED: This study aimed to explore the value of strain elastography (SE) and shear wave elastography (SWE) following the World Federation of Ultrasound in Medicine and Biology (WFUMB) guidelines and recommendations in the real world in distinguishing benign and malignant breast lesions and reducing biopsy of BI-RADS (Breast Imaging Reporting and Data System) 4a lesions.
UNASSIGNED: This prospective study included 274 breast lesions. The elastography score (ES) by the Tsukuba score, the strain ratio (SR) for SE, and Emax for SWE of the lesion(A) and the regions(A\') included the lesion and the margin (0.5-5 mm) surrounding the lesion were measured. The sensitivity, specificity, and AUC were calculated and compared by the cutoff values recommended by WFUMB guidelines.
UNASSIGNED: When scores of 1 to 3 were classified as probably benign by WFUMB recommendation, the ES was significantly higher in malignant lesions compared to benign lesions (p < 0.05) in all lesions. For the cohort by size >20 mm, the sensitivity was 100%, and the specificity was 45.5%. ES had the highest AUC: 0.79(95% CI 0.72-0.86) with a sensitivity of 96.2%, and a specificity of 61.8% for the cohort by size ≤20 mm. For the Emax-A\'-S2.5mm, when the high stiffness would be considered with Emax above 80 kPa in SWE, the malignant lesions were diagnosed with a sensitivity of 95.8%, a specificity of 43.3% for all lesions, a sensitivity of 88.5% for lesions with size ≤20 mm, and sensitivity of 100.0% for lesions with size >20 mm. In 84 lesions of BI-RADS category 4a, if category 4a lesions with ES of 1-3 points or Emax-A\'-S2.5 less than 80 kPa could be downgraded to category 3, 52 (61.9%) lesions could be no biopsy, including two malignancies. If category 4a lesions with ES of 1-3 points and Emax-A\'-S2.5 less than 80kPa could be downgraded to category 3, 23 (27.4%) lesions could be no biopsy, with no malignancy.
UNASSIGNED: The elastography score for SE and Emax-A\' for SWE after our modification were beneficial in the diagnosis of breast cancer. The combination of SWE and SE could effectively reduce the biopsy rate of BI-RADS category 4a lesions.

OBJECTIVE: To compare the diagnostic efficacy of ACR TI-RADS, Kwak TI-RADS, ATA guidelines and KTA/KSThR guidelines in combination with shear wave elastography (SWE) for thyroid nodules.
METHODS: The retrospective study included 566 thyroid nodules with maximum diameter≥5 mm which confirmed by FNA cytology or/and surgical pathology. The sensitivity, specificity, accuracy, Youden index of diagnosis of thyroid nodules by ACR TI-RADS, Kwak TI-RADS, ATA guidelines, KTA/KSThR guidelines and SWE were calculated. The ROC curve was drawn to determine the cut-off values of the four ultrasound classification systems and SWE Emax. The diagnostic efficacy of the four ultrasound classification systems in combination with SWE were calculated and compared with those of pre-combination.
RESULTS: The ROC curves indicated that the cut-off value of ACR TI-RADS, Kwak TI-RADS, ATA guidelines, KTA/KSThR guidelines and Emax of SWE was TR5, 4c, high-suspicion, high-suspicion, and 41.7 kPa, respectively, and the area under the ROC curve (AUC) was 0.907(0.879-0.934), 0904(0.876-0.932), 0.894(0.863-0.924), 0.888(0.856-0.919), 0.886(0.859-0.913), respectively. After combination with SWE, the the sensitivities of the four ultrasound classification systems for the diagnosis of nodules were improved, and the differences were statistically significant (all P≤0.001); the specificities were decreased, but the differences were not statistically significant (all P > 0.05); the accuracies were improved, but only the difference of ACR TI-RADS was statistically significant (x2 = 4.45, P = 0.035); the differences in the AUCs were not significant (all P > 0.05).
CONCLUSIONS: The four ultrasound classification systems and SWE all had high performance in the diagnosis of thyroid nodules. The four classification systems in combination with SWE were all beneficial to the differential diagnosis of nodules, and ACR TI-RADS in combination with SWE was more effective, especially for TR3 and TR4 nodules.

Objective: To evaluate the diagnostic value of the ATA (2015) ultrasound model, shear wave elastography (SWE), and ATA (2015)+SWE combinative modality for the diagnostic efficiency in thyroid nodules with Bethesda Classification Ⅲ indeterminate cytology, determine the diagnostic value of ultrasonography in Bethesda Classification Ⅲ indeterminate cytology.Method:216 thyroid nodules that were initially diagnosed as AUS/FLUS by fine needle aspiration (FNA) were included in this study. The clinical data and two-dimensional ultrasonographic features were compared between the benign and malignant nodules. The two-dimensional ultrasound images of all nodules were sorted by the 2015ATA guideline ultrasound model grading criteria. The maximum and average shear wave velocity (SWV) values were obtained from multiple SWV measurement under the VTIQ speed mode. The optimal threshold drawing from ROC curve and diagnostic performance of single and combinative modality were calculated.Result:①There was no significant difference in age, sex and nodule size between benign and malignant nodules (P>0.05). Malignant nodules of 152 cases of AUS thyroid nodules had significantly higher rates of not well-circumscribed margin and presence of microcalcifications (P=0.005,P=0.004). ②There were significant differences in malignancy risk among the different US patterns defined by the 2015 ATA guidelines in AUS nodules. ③The maximum and mean SWV of AUS/FLUS nodules measured in VTIQ mode were statistically significant in evaluating benign and malignant nodules. ④The area under ROC curves of ATA (2015)+SWE combined mode was 0.912, larger than single diagnosis mode ［ATA (2015):0.854, SWE: 0.862］.Conclusion:SWE can not only compensate for the deficiency of ATA (2015) in the diagnosis of benign and malignant FLUS thyroid nodules, but also effectively improve the diagnostic performance of ATA (2015) in the differentiation of benign and malignant AUS thyroid nodules.

Nowadays, shear wave elastographic techniques have brought a substantial reduction of liver biopsies performed to stage liver fibrosis in patients with chronic hepatitis. The availability of accurate noninvasive methods for the assessment of liver fibrosis was an important breakthrough and prompted ultrasound federations of societies as well as clinical and radiologic societies to issue international guidelines or consensus statements on the clinical applications of shear wave elastographic techniques. This article reviews the guidelines that have been published as of today.

Ultrasound elastography has been introduced into clinical practice for a decade and arisen continuous increasing attention worldwide. Shear wave elastography (SWE) is a further extension of ultrasound elastography on the basis of strain elastography, providing a two-dimensional distribution map of tissue stiffness and quantitative measurement of the tissue stiffness in Young\'s modulus (kPa) and/or shear wave speed (m/s). The Society of Ultrasound in Medicine, Chinese Medical Association (CMA) has recently released a series of guidelines for the use of SWE, including the technique and principle of SWE, and use of SWE in liver fibrosis, breast, thyroid, and musculoskeletal system. Herein, a part of SWE in thyroid nodules is presented. In this guideline, the background, classification and technology of SWE, examination methods, diagnostic performance, prognosis evaluation, reproducibility, and limitations are discussed and recommendations are given. The recommendations are based on the published literatures with regard to SWE with different levels of evidence, particularly a mid-term result of the prospective multi-center clinical trial of SWE in thyroid, as well as the Society of Ultrasound in Medicine, CMA expert\'s consensus. The document provides an overall analysis of SWE in thyroid from clinical perspective, which aimed to provide recommendations to the clinicians with regard to the management of thyroid nodules by the assistance of SWE.

The World Federation for Ultrasound in Medicine and Biology has produced these guidelines for the use of elastography techniques in liver diseases. For each available technique, the reproducibility, results and limitations are analyzed, and recommendations are given. This set of guidelines updates the first version, published in 2015. Since the prior guidelines, there have been several advances in technology. The recommendations are based on the international published literature, and the strength of each recommendation is judged according to the Oxford Centre for Evidence-Based Medicine. The document has a clinical perspective and is aimed at assessing the usefulness of elastography in the management of liver diseases.

The World Federation for Ultrasound in Medicine and Biology (WFUMB) has produced guidelines for the use of elastography techniques including basic science, breast and liver. Here we present elastography in thyroid diseases. For each available technique, procedure, reproducibility, results and limitations are analyzed and recommendations are given. Finally, recommendations are given based on the level of evidence of the published literature and on the WFUMB expert group\'s consensus. The document has a clinical perspective and is aimed at assessing the usefulness of elastography in the management of thyroid diseases.

The World Federation for Ultrasound in Medicine and Biology (WFUMB) has produced guidelines for the use of elastography techniques, including basic science, breast, liver and thyroid elastography. Here we present elastography in prostate diseases. For each available technique, procedure, reproducibility, results and limitations are analyzed and recommendations are given. Finally, recommendations are given based on the level of evidence of the published literature and on the WFUMB expert group\'s consensus. This document has a clinical perspective and is aimed at assessing the usefulness of elastography in the management of prostate diseases.