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Carl D. Malchoff - One of the best experts on this subject based on the ideXlab platform.
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Shear Wave Elastography and parathyroid adenoma: A new tool for diagnosing parathyroid adenomas
European Journal of Radiology, 2016Co-Authors: Ghobad Azizi, Kelé Piper, Michelle L. Mayo, Karly M. Earp, David Puett, James M. Keller, Carl D. MalchoffAbstract:Abstract Objectives This study prospectively determines the Shear Wave Elastography characteristics of parathyroid adenomas using virtual touch imaging quantification, a non-invasive ultrasound based Shear Wave Elastography method. Methods This prospective study examined 57 consecutive patients with biochemically proven primary hyperparathyroidism and solitary parathyroid adenoma identified by ultrasound and confirmed by at least one of the following: surgical resection, positive Technetium–99 m Sestamibi Scintigraphy (MIBI) scan, or fine needle aspiration biopsy with positive PTH washout (performed only in MIBI negative patients). Vascularity and Shear Wave Elastography were performed for all patients. Parathyroid adenoma stiffness was measured as Shear Wave velocity in meters per second. Results The median (range) pre-surgical value for PTH and calcium were 58 pg/mL (19, 427) and 10.8 mg/dL (9.5, 12.1), respectively. 37 patients had positive MIBI scan. 20 patients had negative MIBI scan but diagnosis was confirmed with positive PTH washout. 42 patients underwent parathyroidectomy, and an adenoma was confirmed in all. The median (range) Shear Wave velocity for all parathyroid adenomas enrolled in this study was 2.02 m/s (1.53, 2.50). The median (range) Shear Wave velocity for thyroid tissue was 2.77 m/s (1.89, 3.70). The Shear Wave velocity of the adenomas was independent of adenoma size, serum parathyroid hormone concentration, or plasma parathyroid hormone concentration. Conclusions Tissue elasticity of parathyroid adenoma is significantly lower than thyroid tissue. B-mode features and distinct vascularity pattern are helpful tools in diagnosing parathyroid adenoma with ultrasound. Shear Wave Elastography may provide valuable information in diagnosing parathyroid adenoma.
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Shear Wave Elastography and parathyroid adenoma: A new tool for diagnosing parathyroid adenomas
European journal of radiology, 2016Co-Authors: Ghobad Azizi, Kelé Piper, Michelle L. Mayo, Karly M. Earp, David Puett, James M. Keller, Carl D. MalchoffAbstract:This study prospectively determines the Shear Wave Elastography characteristics of parathyroid adenomas using virtual touch imaging quantification, a non-invasive ultrasound based Shear Wave Elastography method. This prospective study examined 57 consecutive patients with biochemically proven primary hyperparathyroidism and solitary parathyroid adenoma identified by ultrasound and confirmed by at least one of the following: surgical resection, positive Technetium-99m Sestamibi Scintigraphy (MIBI) scan, or fine needle aspiration biopsy with positive PTH washout (performed only in MIBI negative patients). Vascularity and Shear Wave Elastography were performed for all patients. Parathyroid adenoma stiffness was measured as Shear Wave velocity in meters per second. The median (range) pre-surgical value for PTH and calcium were 58pg/mL (19, 427) and 10.8mg/dL (9.5, 12.1), respectively. 37 patients had positive MIBI scan. 20 patients had negative MIBI scan but diagnosis was confirmed with positive PTH washout. 42 patients underwent parathyroidectomy, and an adenoma was confirmed in all. The median (range) Shear Wave velocity for all parathyroid adenomas enrolled in this study was 2.02m/s (1.53, 2.50). The median (range) Shear Wave velocity for thyroid tissue was 2.77m/s (1.89, 3.70). The Shear Wave velocity of the adenomas was independent of adenoma size, serum parathyroid hormone concentration, or plasma parathyroid hormone concentration. Tissue elasticity of parathyroid adenoma is significantly lower than thyroid tissue. B-mode features and distinct vascularity pattern are helpful tools in diagnosing parathyroid adenoma with ultrasound. Shear Wave Elastography may provide valuable information in diagnosing parathyroid adenoma. Copyright © 2016 The Author(s). Published by Elsevier Ireland Ltd.. All rights reserved.
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Shear Wave Elastography and Cervical Lymph Nodes: Predicting Malignancy
Ultrasound in medicine & biology, 2016Co-Authors: Ghobad Azizi, Kelé Piper, Michelle L. Mayo, Karly M. Earp, David Puett, James M. Keller, Carl D. MalchoffAbstract:This prospective study evaluates the accuracy of virtual touch imaging quantification (VTIQ), a non-invasive Shear Wave Elastography method for measuring cervical lymph nodes (LN) stiffness in differentiating benign from malignant LN. The study evaluated 270 LN in 236 patients with both conventional B-mode ultrasound and VTIQ Shear Wave Elastography before fine-needle aspiration biopsy (FNAB). LN stiffness was measured as Shear Wave velocity (SWV) in m/s. Surgical resection was advised for FNAB results that were not clearly benign. Surgical pathology confirmed 54 malignant LN. The receiver operating curve (ROC) identified a single cut-off value of 2.93 m/s as the maximum SWV for predicting a malignant cervical LN. The sensitivity and specificity were 92.59% and 75.46%, respectively. Positive predictive value (PPV) was 48.54% and negative predictive value (NPV) was 97.60%. LN stiffness measured by VTIQ-generated Shear Wave Elastography is an independent predictor of malignancy.
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Thyroid Nodules and Shear Wave Elastography: A New Tool in Thyroid Cancer Detection.
Ultrasound in medicine & biology, 2015Co-Authors: Ghobad Azizi, Kelé Piper, Michelle L. Mayo, Karly M. Earp, David Puett, James M. Keller, Carl D. MalchoffAbstract:This study determines the performance of virtual touch imaging quantification (VTIQ), a non-invasive Shear Wave Elastography method for measuring thyroid nodule (TN) stiffness, in distinguishing benign from malignant TNs. This prospective study evaluates 707 TNs in 676 patients with fine-needle aspiration biopsy (FNAB). Before FNAB, both conventional B-mode ultrasound and Shear Wave Elastography were performed. Surgical resection was recommended for FNAB results that were not clearly benign. Surgical pathology confirmed 82 malignant TNs. The receiver operating curve identified a single cut-off of 3.54 m/s as the maximum Shear Wave velocity (SWV) for predicting thyroid cancer (TC). The sensitivity and specificity were 79.27% and 71.52%, respectively. Positive predictive value (PPV) was 26.75% and negative predictive value (NPV) was 96.34%. Compared with B-mode US features for predicting malignancy, SWV ≥3.54 m/s has a higher sensitivity, specificity, PPV and NPV. TN stiffness measured by VTIQ-generated Shear Wave Elastography is an independent predictor of TC.
Chung-li Wang - One of the best experts on this subject based on the ideXlab platform.
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Spatial-dependent mechanical properties of the heel pad by Shear Wave Elastography
Journal of biomechanics, 2017Co-Authors: Che-yu Lin, Pei-yu Chen, Yio-wha Shau, Hao-chih Tai, Chung-li WangAbstract:The heel pad plays an important role in gait, and its biomechanical behavior and functionality are determined by its specialized architecture and mechanical properties. The purpose of this study was to apply supersonic Shear Wave Elastography, an ultrasound-based noninvasive modality that can quantitatively estimate the Shear stiffness of the tissue, to investigate the spatial-dependent mechanical properties of the heel pad. Measurements were conducted in 40 heel pads of 20 normal participants aged between 20 and 30 years by Shear Wave Elastography. The continuous change in local Shear stiffness of the heel pad along the depth direction of the heel pad was measured. The result showed that the mechanical properties of the heel pad were highly heterogeneous but followed a simple and specific pattern that local heel pad Shear stiffness was highest beneath the plantar skin and decreased continuously with increasing depth. This finding provides a better understanding of the heel pad biomechanics and basis for further investigation of the heterogeneous properties of the heel pad.
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An Artifact in Supersonic Shear Wave Elastography
Ultrasound in medicine & biology, 2016Co-Authors: Che-yu Lin, Pei-yu Chen, Yio-wha Shau, Chung-li WangAbstract:Supersonic Shear Wave Elastography is a novel ultrasound technology that allows objective evaluation of soft tissue stiffness. The purpose of this study is to report an artifact in supersonic Shear Wave Elastography that may strongly affect the accuracy and quality of the measurement of soft tissue stiffness, and to step-by-step describe how the artifact was found and how it was verified by a series of experiments under different conditions. There were a total of three longitudinal band-like artifacts, 1.3 cm apart from each other on the entire image along the length of the SuperLinear SL15-4 transducer surface, with the middle one at the center of the image. When using supersonic Shear Wave Elastography, users should be keenly aware of the possible occurrence of the artifact and avoid it by choosing the quantification measurement regions of interest (ROIs) away from the artifact regions.
Yasuhide Yoshitake - One of the best experts on this subject based on the ideXlab platform.
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Validity of Measurement of Shear Modulus by Ultrasound Shear Wave Elastography in Human Pennate Muscle
PloS one, 2015Co-Authors: Naokazu Miyamoto, Hiroaki Kanehisa, Kosuke Hirata, Yasuhide YoshitakeAbstract:Ultrasound Shear Wave Elastography is becoming a valuable tool for measuring mechanical properties of individual muscles. Since ultrasound Shear Wave Elastography measures Shear modulus along the principal axis of the probe (i.e., along the transverse axis of the imaging plane), the measured Shear modulus most accurately represents the mechanical property of the muscle along the fascicle direction when the probe's principal axis is parallel to the fascicle direction in the plane of the ultrasound image. However, it is unclear how the measured Shear modulus is affected by the probe angle relative to the fascicle direction in the same plane. The purpose of the present study was therefore to examine whether the angle between the principal axis of the probe and the fascicle direction in the same plane affects the measured Shear modulus. Shear modulus in seven specially-designed tissue-mimicking phantoms, and in eleven human in-vivo biceps brachii and medial gastrocnemius were determined by using ultrasound Shear Wave Elastography. The probe was positioned parallel or 20° obliquely to the fascicle across the B-mode images. The reproducibility of Shear modulus measurements was high for both parallel and oblique conditions. Although there was a significant effect of the probe angle relative to the fascicle on the Shear modulus in human experiment, the magnitude was negligibly small. These findings indicate that the ultrasound Shear Wave Elastography is a valid tool for evaluating the mechanical property of pennate muscles along the fascicle direction.
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muscle Shear modulus measured with ultrasound Shear Wave Elastography across a wide range of contraction intensity
Muscle & Nerve, 2014Co-Authors: Yasuhide Yoshitake, Yohei Takai, Hiroaki Kanehisa, Minoru ShinoharaAbstract:Introduction: In this study we examine the repeat- ability of measuring muscle Shear modulus using ultrasound Shear-Wave Elastography between trials and between days, and the association between Shear modulus and contraction inten- sity over a wide range of intensities. Methods: Shear modulus of the biceps brachii was determined using ultrasound Shear- Wave Elastography during static elbow flexion (up to 60% of maximal contraction) in healthy young adults. Results: The cor- respondence of Shear modulus was confirmed in phantoms between the manufacturer-calibrated values and the Shear- Wave Elastography values. The intraclass correlation coefficient of muscle Shear modulus was high: 0.978 between trials and 0.948 between days. Shear modulus increased linearly with elbow flexion torque across contraction intensity, and its slope was associated negatively with muscle strength. Conclusions: Muscle Shear modulus measured with ultrasound Shear-Wave Elastography may be useful for inferring muscle stiffness across a wide range of contraction intensity. In addition, it has high repeatability between trials and between days. Muscle Nerve 50: 103-113, 2014
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Muscle Shear modulus measured with ultrasound Shear‐Wave Elastography across a wide range of contraction intensity
Muscle & nerve, 2014Co-Authors: Yasuhide Yoshitake, Yohei Takai, Hiroaki Kanehisa, Minoru ShinoharaAbstract:Introduction: In this study we examine the repeat- ability of measuring muscle Shear modulus using ultrasound Shear-Wave Elastography between trials and between days, and the association between Shear modulus and contraction inten- sity over a wide range of intensities. Methods: Shear modulus of the biceps brachii was determined using ultrasound Shear- Wave Elastography during static elbow flexion (up to 60% of maximal contraction) in healthy young adults. Results: The cor- respondence of Shear modulus was confirmed in phantoms between the manufacturer-calibrated values and the Shear- Wave Elastography values. The intraclass correlation coefficient of muscle Shear modulus was high: 0.978 between trials and 0.948 between days. Shear modulus increased linearly with elbow flexion torque across contraction intensity, and its slope was associated negatively with muscle strength. Conclusions: Muscle Shear modulus measured with ultrasound Shear-Wave Elastography may be useful for inferring muscle stiffness across a wide range of contraction intensity. In addition, it has high repeatability between trials and between days. Muscle Nerve 50: 103-113, 2014
Ghobad Azizi - One of the best experts on this subject based on the ideXlab platform.
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Shear Wave Elastography and parathyroid adenoma: A new tool for diagnosing parathyroid adenomas
European Journal of Radiology, 2016Co-Authors: Ghobad Azizi, Kelé Piper, Michelle L. Mayo, Karly M. Earp, David Puett, James M. Keller, Carl D. MalchoffAbstract:Abstract Objectives This study prospectively determines the Shear Wave Elastography characteristics of parathyroid adenomas using virtual touch imaging quantification, a non-invasive ultrasound based Shear Wave Elastography method. Methods This prospective study examined 57 consecutive patients with biochemically proven primary hyperparathyroidism and solitary parathyroid adenoma identified by ultrasound and confirmed by at least one of the following: surgical resection, positive Technetium–99 m Sestamibi Scintigraphy (MIBI) scan, or fine needle aspiration biopsy with positive PTH washout (performed only in MIBI negative patients). Vascularity and Shear Wave Elastography were performed for all patients. Parathyroid adenoma stiffness was measured as Shear Wave velocity in meters per second. Results The median (range) pre-surgical value for PTH and calcium were 58 pg/mL (19, 427) and 10.8 mg/dL (9.5, 12.1), respectively. 37 patients had positive MIBI scan. 20 patients had negative MIBI scan but diagnosis was confirmed with positive PTH washout. 42 patients underwent parathyroidectomy, and an adenoma was confirmed in all. The median (range) Shear Wave velocity for all parathyroid adenomas enrolled in this study was 2.02 m/s (1.53, 2.50). The median (range) Shear Wave velocity for thyroid tissue was 2.77 m/s (1.89, 3.70). The Shear Wave velocity of the adenomas was independent of adenoma size, serum parathyroid hormone concentration, or plasma parathyroid hormone concentration. Conclusions Tissue elasticity of parathyroid adenoma is significantly lower than thyroid tissue. B-mode features and distinct vascularity pattern are helpful tools in diagnosing parathyroid adenoma with ultrasound. Shear Wave Elastography may provide valuable information in diagnosing parathyroid adenoma.
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Shear Wave Elastography and parathyroid adenoma: A new tool for diagnosing parathyroid adenomas
European journal of radiology, 2016Co-Authors: Ghobad Azizi, Kelé Piper, Michelle L. Mayo, Karly M. Earp, David Puett, James M. Keller, Carl D. MalchoffAbstract:This study prospectively determines the Shear Wave Elastography characteristics of parathyroid adenomas using virtual touch imaging quantification, a non-invasive ultrasound based Shear Wave Elastography method. This prospective study examined 57 consecutive patients with biochemically proven primary hyperparathyroidism and solitary parathyroid adenoma identified by ultrasound and confirmed by at least one of the following: surgical resection, positive Technetium-99m Sestamibi Scintigraphy (MIBI) scan, or fine needle aspiration biopsy with positive PTH washout (performed only in MIBI negative patients). Vascularity and Shear Wave Elastography were performed for all patients. Parathyroid adenoma stiffness was measured as Shear Wave velocity in meters per second. The median (range) pre-surgical value for PTH and calcium were 58pg/mL (19, 427) and 10.8mg/dL (9.5, 12.1), respectively. 37 patients had positive MIBI scan. 20 patients had negative MIBI scan but diagnosis was confirmed with positive PTH washout. 42 patients underwent parathyroidectomy, and an adenoma was confirmed in all. The median (range) Shear Wave velocity for all parathyroid adenomas enrolled in this study was 2.02m/s (1.53, 2.50). The median (range) Shear Wave velocity for thyroid tissue was 2.77m/s (1.89, 3.70). The Shear Wave velocity of the adenomas was independent of adenoma size, serum parathyroid hormone concentration, or plasma parathyroid hormone concentration. Tissue elasticity of parathyroid adenoma is significantly lower than thyroid tissue. B-mode features and distinct vascularity pattern are helpful tools in diagnosing parathyroid adenoma with ultrasound. Shear Wave Elastography may provide valuable information in diagnosing parathyroid adenoma. Copyright © 2016 The Author(s). Published by Elsevier Ireland Ltd.. All rights reserved.
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Shear Wave Elastography and Cervical Lymph Nodes: Predicting Malignancy
Ultrasound in medicine & biology, 2016Co-Authors: Ghobad Azizi, Kelé Piper, Michelle L. Mayo, Karly M. Earp, David Puett, James M. Keller, Carl D. MalchoffAbstract:This prospective study evaluates the accuracy of virtual touch imaging quantification (VTIQ), a non-invasive Shear Wave Elastography method for measuring cervical lymph nodes (LN) stiffness in differentiating benign from malignant LN. The study evaluated 270 LN in 236 patients with both conventional B-mode ultrasound and VTIQ Shear Wave Elastography before fine-needle aspiration biopsy (FNAB). LN stiffness was measured as Shear Wave velocity (SWV) in m/s. Surgical resection was advised for FNAB results that were not clearly benign. Surgical pathology confirmed 54 malignant LN. The receiver operating curve (ROC) identified a single cut-off value of 2.93 m/s as the maximum SWV for predicting a malignant cervical LN. The sensitivity and specificity were 92.59% and 75.46%, respectively. Positive predictive value (PPV) was 48.54% and negative predictive value (NPV) was 97.60%. LN stiffness measured by VTIQ-generated Shear Wave Elastography is an independent predictor of malignancy.
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Thyroid Nodules and Shear Wave Elastography: A New Tool in Thyroid Cancer Detection.
Ultrasound in medicine & biology, 2015Co-Authors: Ghobad Azizi, Kelé Piper, Michelle L. Mayo, Karly M. Earp, David Puett, James M. Keller, Carl D. MalchoffAbstract:This study determines the performance of virtual touch imaging quantification (VTIQ), a non-invasive Shear Wave Elastography method for measuring thyroid nodule (TN) stiffness, in distinguishing benign from malignant TNs. This prospective study evaluates 707 TNs in 676 patients with fine-needle aspiration biopsy (FNAB). Before FNAB, both conventional B-mode ultrasound and Shear Wave Elastography were performed. Surgical resection was recommended for FNAB results that were not clearly benign. Surgical pathology confirmed 82 malignant TNs. The receiver operating curve identified a single cut-off of 3.54 m/s as the maximum Shear Wave velocity (SWV) for predicting thyroid cancer (TC). The sensitivity and specificity were 79.27% and 71.52%, respectively. Positive predictive value (PPV) was 26.75% and negative predictive value (NPV) was 96.34%. Compared with B-mode US features for predicting malignancy, SWV ≥3.54 m/s has a higher sensitivity, specificity, PPV and NPV. TN stiffness measured by VTIQ-generated Shear Wave Elastography is an independent predictor of TC.
Carlo Filice - One of the best experts on this subject based on the ideXlab platform.
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Performance and cutoffs for liver fibrosis staging of a two-dimensional Shear Wave Elastography technique.
European journal of gastroenterology & hepatology, 2020Co-Authors: Giovanna Ferraioli, Laura Maiocchi, Carolina Dellafiore, Carmine Tinelli, Elisabetta Above, Carlo FiliceAbstract:OBJECTIVES To assess performance and cutoffs of the 2-dimensional Shear Wave Elastography technique available on the Aplio i800 ultrasound system (Canon Medical Systems, Japan), using transient Elastography as reference standard, and to assess the correlation of Shear-Wave-speed dispersion with liver fibrosis or steatosis. METHODS This was a single-center cross-sectional study. The correlations between values obtained with transient Elastography and 2-dimensional-Shear Wave Elastography, and between Shear-Wave-speed dispersion and fibrosis or steatosis, were assessed with Pearson's r. The diagnostic performance of the 2-dimensional-Shear Wave Elastography for staging significant fibrosis and severe fibrosis compared to transient Elastography was assessed using the area under the receiver operating characteristic curve analysis. RESULTS Three hundred sixty-seven patients (198 males and 169 females) were studied. There was a high correlation between 2-dimensional-Shear Wave Elastography and transient Elastography (r = 0.87, P 7 and > 9 kPa. Shear-Wave-speed dispersion showed a high correlation with fibrosis (r = 0.85, P < 0.0001), whereas there was a very weak correlation with steatosis. CONCLUSIONS The results of this study show that this 2-dimensional-Shear Wave Elastography technique is accurate for staging liver fibrosis. Shear-Wave-speed dispersion is highly correlated with liver fibrosis but not with steatosis.
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Shear Wave Elastography for evaluation of liver fibrosis.
Journal of ultrasound in medicine : official journal of the American Institute of Ultrasound in Medicine, 2014Co-Authors: Giovanna Ferraioli, Parth J. Parekh, Alexander Levitov, Carlo FiliceAbstract:The prognosis and management of chronic viral hepatitis mainly depend on the extent of liver fibrosis, particularly in chronic hepatitis C. Liver histologic analysis is still considered the reference standard in the assessment of liver fibrosis despite the interobserver and interobserver variability in staging and some morbidity and mortality risks. Thus, noninvasive methods for assessing liver fibrosis are of great clinical interest. In the last decade, ultrasound-based techniques to estimate the stage of liver fibrosis have become commercially available. They all have the capability to noninvasively evaluate differences in the elastic properties of soft tissues by measuring tissue behavior when a mechanical stress is applied. Shear Wave Elastography relies on the generation of Shear Waves determined by the displacement of tissues induced by the force of a focused ultrasound beam or by an external push. This article reviews the results that have been obtained with Shear Wave Elastography for assessment of liver fibrosis.
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Reproducibility of real-time Shear Wave Elastography in the evaluation of liver elasticity
European journal of radiology, 2012Co-Authors: Giovanna Ferraioli, Carmine Tinelli, Elisabetta Above, Mabel Zicchetti, Gianluigi Poma, Marta Di Gregorio, Carlo FiliceAbstract: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.
