Assessment of Virtual Touch Tissue Imaging Quantification and the Ultrasound Thyroid Imaging Reporting and Data System in Patients With Thyroid Nodules Referred for Biopsy.

OBJECTIVES: To evaluate the diagnostic performance of Virtual Touch tissue imaging quantification (VTIQ; Siemens Medical Solutions, Mountain View, CA) in combination with the Thyroid Imaging Reporting and Data System (TI-RADS) for assessing thyroid nodules referred for biopsy. METHODS: A total of 197 surgically or cytologically proven thyroid nodules in 187 patients were included. Nodules evaluated by conventional ultrasound (US) and VTIQ examinations were classified into US TI-RADS categories. The shear wave velocity (SWV) on VTIQ was assessed, and the cutoff value was obtained from a receiver operating characteristic curve analysis. Diagnostic performances of conventional US, VTIQ, and their combination were compared. RESULTS: There were 134 benign and 63 malignant nodules. The sensitivity and specificity for the US TI-RADS were 98.4% and 20.1%, respectively. The areas under the receiver operating characteristic curves for the mean, maximum, minimum, and ratio of the SWV were 0.818, 0.805, 0.799, and 0.728. With a cutoff value of 2.90 m/s, the sensitivity and specificity of the mean SWV were 71.4% and 82.8%. By applying this value or less as a standard for downgrading TI-RADS category 4a to category 3 lesions, the specificity significantly rose from 20.1% to 47.0% (P < .001) without a loss of sensitivity. CONCLUSIONS: The additional application of VTIQ can improve the specificity of the TI-RADS for evaluating thyroid nodules without a loss of sensitivity.

Virtual Touch Tissue Imaging and Quantification in the Evaluation of Thyroid Nodules.

OBJECTIVES: To investigate the diagnostic performance of a 2-dimensional shear wave elastographic technique (Virtual Touch tissue imaging and quantification [VTIQ]; Siemens Medical Solutions, Mountain View, CA) for predicting thyroid malignancy. METHODS: A total of 302 thyroid nodules underwent conventional sonography and VTIQ before fine-needle aspiration examination or surgery. Compared with histopathologic or cytologic results in combination with follow-up, the diagnostic performance of various shear wave speed (SWS) indices (minimum [SWSmin ], maximum [SWSmax ], and mean [SWSmean ]) on VTIQ as well as conventional sonographic features for predicting thyroid malignancy was evaluated in all of the nodules. RESULTS: Sixty-five malignant and 237 benign thyroid nodules were histopathologically or cytologically confirmed. All SWS indices on VTIQ were lower in benign nodules than thyroid malignancy (all P < .001). For discrimination between malignant and benign nodules, all VTIQ SWS indices were better than conventional sonographic features, such as a solid component, a taller-than-wide shape, microcalcification, a poorly defined margin and hypoechogenicity, in predicting thyroid malignancy (all P < .05). By applying a cutoff SWSmean value of 2.60 m/s, VTIQ achieved sensitivity and negative predictive values of 84.6% and 94.3%, respectively, for differentiating nodules. The areas under the receiver operating characteristic curve of SWSmax (0.862 versus 0.717), SWSmin (0.866 versus 0.717), and SWSmean (0.891 versus 0.725) for nodules larger than 10 mm were higher than those for nodules of 10 mm or smaller (all P < .05). Interoperator and intraoperator reproducibility was proven to be excellent, with all interclass correlation coefficient values higher than 0.80 (range, 0.813-0.905) CONCLUSIONS: Virtual Touch tissue imaging and quantification is a useful and reproducible tool for predicting thyroid malignancy.

Initial Experience With Ultrasound Elastography for Diagnosis of Major Salivary Gland Lesions.

OBJECTIVES: The aim of this study was to evaluate the usefulness of ultrasound elastography, including conventional strain elastography, acoustic radiation force impulse (ARFI)-induced strain elastography, and point shear wave elastography (SWE) for diagnosis of major salivary gland lesions. METHODS: Forty major salivary gland lesions underwent conventional sonography, conventional strain elastography, ARFI strain elastography, and point SWE before surgery or biopsy. The diagnostic performances of the sonographic and elastographic techniques were assessed with reference to histopathologic results. RESULTS: There were 32 benign (7 Warthin tumors, 17 pleomorphic adenomas, and 8 other benign lesions) and 8 malignant (1 squamous carcinoma, 2 metastases, 2 mucoepidermoid carcinomas, 1 anaplastic carcinoma, and 2 malignant lymphomas) major salivary gland lesions on pathologic analysis. No conventional sonographic features or conventional strain elastographic scores were found to be associated with malignancy (all P > .05). The ARFI strain elastographic scores between benign and malignant lesions were statistically different (P = .032) and an ARFI strain elastographic score of 4 or greater was highly predictive of malignancy (P= .025). An ARFI strain elastographic score of greater than 3 achieved specificity of 81.3% (26 of 32) and sensitivity of 62.5% (5 of 8) in differentiating benign from malignant lesions. The shear wave velocity on point SWE did not show a significant difference in distinguishing between malignant and benign lesions (6.07 versus 4.43 m/s; P > .05). However, Warthin tumors had a trend to show lower shear wave velocities compared with pleomorphic adenomas (2.84 versus 5.27 m/s; P = .024). CONCLUSIONS: Acoustic radiation force impulse strain elastography may be potentially useful for diagnosing major salivary gland lesions, whereas conventional strain elastography and point SWE are not helpful.

Predicting tall-cell subtype of papillary thyroid carcinomas independently with preoperative multimodal ultrasound.

OBJECTIVES: This study aimed to explore the differences between tall-cell subtype of papillary thyroid carcinoma (TCPTC) and classical papillary thyroid carcinoma (cPTC) using multimodal ultrasound, and identify independent risk factors for TCPTC to compensate the deficiency of preoperative cytological and molecular diagnosis on PTC subtypes. METHODS: Forty-six TCPTC patients and 92 cPTC patients were included. Each patient received grey-scale ultrasound, colour Dopplor flow imaging (CDFI) and shear-wave elastography (SWE) preoperatively. Clinicopathologic information, grey-scale ultrasound features, CDFI features and SWE features of 98 lesions were compared using univariate analysis to find out predictors of TCPTC, based on which, a predictive model was built to differentiate TCPTC from cPTC and validated with 40 patients. RESULTS: Univariate and multivariate analyses identified that extra-thyroidal extension (odds ratio [OR], 15.12; 95% CI, 2.26-115.44), aspect ratio (≥0.91) (OR, 29.34; 95% CI, 1.29-26.23), and maximum diameter ≥14.6 mm (OR, 20.79; 95% CI, 3.87-111.47) were the independent risk factors for TCPTC. Logistic regression equation: P = 1/1+ExpΣ[-5.099 + 3.004 × (if size ≥14.6 mm) + 2.957 × (if aspect ratio ≥ 0.91) + 2.819 × (if extra-thyroidal extension). The prediction model had a good discrimination performance for TCPTC: the area under the receiver-operator-characteristic curve, sensitivity, and specificity were 0.928, 0.848, and 0.954 in cohort 1, and the corresponding values in cohort 2 were 0.943, 0.923, and 0.926, respectively. CONCLUSION: Ultrasound has the potential for differential diagnosis of TCPTC from cPTC. A prediction model based on ultrasound characteristics (extra-thyroidal extension, aspect ratio ≥0.91, and maximum diameter ≥14.6 mm) was useful in predicting TCPTC. ADVANCES IN KNOWLEDGE: Multimodal ultrasound prediction of TCPTC was a supplement to preoperative cytological diagnosis and molecular diagnosis of PTC subtypes.

Added value of contrast-enhanced ultrasound to conventional ultrasound for characterization of indeterminate soft-tissue tumors.

OBJECTIVE: To assess the added value of contrast-enhanced ultrasound (CEUS) to conventional ultrasound in differentiating benign soft-tissue tumors from malignant ones. METHODS: 197 soft-tissue tumors underwent ultrasound examination with confirmed histopathology were retrospectively evaluated. The radiologists classified all the tumors as benign, malignant, or indeterminate according to ultrasound features. The indeterminate tumors underwent CEUS were reviewed afterwards for malignancy identification by using individual and combined CEUS features. RESULTS: Ultrasound analysis classified 62 soft-tissue tumors as benign, 111 tumors as indeterminate and 24 tumors as malignant. There 104 indeterminate tumors were subject to CEUS. Three CEUS features including enlargement of enhancement area, infiltrative enhancement boundary, and intratumoral arrival time difference were significantly associated with the tumor nature in both univariable and multivariable analysis for the indeterminate tumors (all p < 0.05). When at least one out of the three discriminant CEUS features were present, the best sensitivity of 100% for malignancy identification was obtained with the specificity of 66.7% and the AUC of 0.833. When at least two of the three discriminant CEUS features were present, the best area under the receiver operating characteristic curve (AUC) of 0.924 for malignancy identification was obtained. The combination of at least two discriminant CEUS features showed much better diagnostic performance than the optimal combination of ultrasound features in terms of AUC (0.924 vs 0.608, p < 0.0001), sensitivity (94.0% vs 42.0%, p < 0.0001), and specificity (90.7% vs 79.6%, p = 0.210) for the indeterminate tumors. CONCLUSION: The combination CEUS features of enlargement of enhancement area, infiltrative enhancement boundary and intratumoral arrival time difference are valuable to improve the discriminating performance for indeterminate soft-tissue tumors on conventional ultrasound. ADVANCES IN KNOWLEDGE: The combination of peritumoral and arrival-time CEUS features can improve the discriminating performance for indeterminate soft-tissue tumors on conventional ultrasound.

Predicting malignancy in thyroid nodules based on conventional ultrasound and elastography: the value of predictive models in a multi-center study.

BACKGROUND: This study aimed to establish predictive models based on features of Conventional Ultrasound (CUS) and elastography in a multi-center study to determine appropriate preoperative diagnosis of malignancy in thyroid nodules with different risk stratification based on 2017 Thyroid Imaging Reporting and Data System by the American College of Radiology (ACR TI-RADS) guidelines. METHODS: Five hundred forty-eight thyroid nodules from three centers pathologically confirmed by the cytology or histology were retrospectively enrolled in the study, which were examined by CUS and elastography before fine needle aspiration (FNA) and surgery. Characteristics of CUS of thyroid nodules were reviewed according to 2017 ACR TI-RADS. Binary logistic regression analysis was used to develop the prediction models based on the different risk stratification of CUS features and elastography which were statistically significant. Values of predictive models were evaluated regarding the discrimination and calibration. RESULTS: Binary logistic regression showed that patients' age, taller-than-wider, lobulated or irregular boundary, extra-thyroid extension, microcalcification and the elastic parameter of Virtual touch tissue imaging quantification (VTIQ) max were independent predictors for thyroid malignancy (p < 0.05) in the ACR model and showed the area under the curve (AUC) in training (0.912) and validation cohort (internal and external: 0.877 vs 0.935). Predictive models showed predictors in ACR TR4 and TR5 for malignancy and diagnostic performance of AUC in training, internal and external validation cohort respectively: the VTIQ max (p < 0.001) with AUC of 0.809 vs 0.842 vs 0.705 and the age, taller than wide, VTIQ max variables with AUC of 0.859 vs 0.830 vs 0.906 in validation cohort. All predictive models have better calibration capabilities (p > 0.05). CONCLUSIONS: Predictive models combined CUS and elastography features would aid clinicians to make appropriate preoperative diagnosis of thyroid nodules among different risk stratification. The elastography parameter of VTIQ max has the priority in distinguishing thyroid malignancy with moderately suspicious (ACR TR4).

Conventional ultrasound characteristics, TI-RADS category and shear wave speed measurement between follicular adenoma and follicular thyroid carcinoma.

The purpose of the study was to explore the differences of conventional ultrasound characteristics, thyroid imaging reporting and data system (TI-RADS) category and shear wave speed (SWS) measurement between follicular adenoma (FA) and follicular thyroid carcinoma (FTC). Twenty-eight FTCs and 67 FAs proven by surgery were retrospectively included for analysis. Conventional ultrasound and point-shear wave elastography (p-SWE) were performed in all of the included patients. The ultrasound features, American Thyroid Association (ATA) TI-RADS category and American College of Radiology (ACR) TI-RADS category, SWS measurement were compared between the two groups. Receiver operating characteristic (ROC) curve was performed and area under ROC curve (AUC) was obtained for significant features. There were no statistical differences in mean age (46.9±15.7years vs. 48.6±13.6years, P = 0.639), gender (9 males, 32.1% vs. 18 males, 29.0%, P = 0.766) and mean diameter (28.3±16.2 mm vs. 33.8±11.9 mm, P = 0.077) between FTCs and FAs. Hypoechogenicity, lobulated or irregular margin, macrocalcification were more common in FTCs than FAs (all P < 0.05). Mean SWS of FTCs (2.29±0.64 m/s) was slightly higher than that of FAs (1.94±0.68 m/s) (P = 0.023). The AUCs were 0.655, 0.744, and 0.744 with the cut-off SWS≥1.89 m/s, ACR TI-RADS category 4 and intermediate suspicion of ATA TI-RADS category. The sensitivity and AUC were 82.1% and 0.812 with combined ultrasound features of hypoechogenicity, lobulated or irregular margin and macrocalcification. In Conclusion, SWS measurement and TI-RADS categories were useful for the identification of FTCs from FAs.

Comparisons of ACR TI-RADS, ATA guidelines, Kwak TI-RADS, and KTA/KSThR guidelines in malignancy risk stratification of thyroid nodules.

OBJECTIVE: To compare the diagnostic performance and the unnecessary biopsy rates for recommending fine needle aspiration (FNA) of Thyroid Imaging Reporting and Data Systems proposed by American College of Radiology (ACR TI-RADS), American Thyroid Association (ATA) guidelines, TI-RADS proposed by Kwak (Kwak TI-RADS), and Korean Thyroid Association/Korean Society of Thyroid Radiology (KTA/KSThR) guidelines for malignancy risk stratification of thyroid nodules (TNs). METHODS: The study included 1271 TNs whose cytologic results or surgical pathologic findings were available. Ultrasound images of these TNs were retrospectively reviewed and categorized according to the four guidelines. The diagnostic performances and the unnecessary biopsy rates for recommending FNA of the four guidelines were evaluated. RESULTS: After multivariate analysis, the most significant independent predictor for malignancy was hypoechogenicity/marked hypoechogenicity (OR: 9.37, 95% CI: 5.40-16.26) (P < 0.001) among the suspicious ultrasound images features. For all nodules and two subgroups (i.e. nodules <10 mm group and nodules ≥10 mm group), ACR TI-RADS demonstrated higher specificities (all P < 0.05) and lower sensitivities (all P < 0.001) than the other guidelines. In the all nodules group and the nodules<10 mm group, ACR TI-RADS and Kwak TI-RADS had higher Azs than the other guidelines (all P < 0.01). The unnecessary biopsy rates for recommending FNA of ACR TI-RADS in the all nodules (≥10 mm) group and the subgroup (10∼19 mm) were all lower than those of the others guidelines (P < 0.001 for all). For the subgroup (≥20 mm), the unnecessary biopsy rate of ACR was lower than that of ATA guidelines and KTA/KSThR guidelines (P < 0.001). CONCLUSIONS: The four guidelines have good diagnostic efficiency in differentiating TNs. ACR TI-RADS and Kwak TI-RADS have better diagnostic performance than the other guidelines in the all nodules group and the nodules<10 mm group. Considering the comprehensive diagnostic efficacy and unnecessary biopsy rate, ACR TI-RADS is a more desirable classification guideline in clinical practice.

Stiffness distribution in the ablated zone after radiofrequency ablation for liver: An ex-vivo study with a tissue elastometer.

OBJECTIVE: To investigate the stiffness distribution in the ablated zone after radiofrequency ablation (RFA), we used a device called tissue elastometer based on gross liver samples. MATERIALS: AND METHODS: Twelve freshly excised porcine livers were subject to RFA under a same setup to form elliptic ablated samples. Each sample was cut open for gross examination, and then the surface of the section plane was sliced into one piece for Young's modulus test using the tissue elastometer. Five test points along the long- and short-axis on each piece were selected to evaluate stiffness distribution respectively. Among them, four points distributed equidistantly from center to boundary in the ablated zone and one was in the unablated zone. RESULTS: In the ablated zone, we found the Young's moduli were significantly different among the four test points both in long- (F = 99.04, p <0.001) and short-axis (F = 79.47, p <0.001) directions. The Young's modulus showed a downtrend in each direction, and was linearly related to the distance from the center to the test point (for long axis, R2 = 0.968; for short axis, R2 = 0.984, both p <0.001). A more significant downtrend was observed in short-axis direction. The Young's moduli gained from the inner edge of ablated zone were comparable and significantly higher than those from the outer edge for both directions. The maximum value of 24.71kPa for Young's modulus was the appropriate threshold to ensure the tissues were necrotic completely. CONCLUSION: The stiffness inside the ablated zone represented a radial distribution with downtrend, following a linear law. The stiffness at the inner edge of ablated zone is stable and significantly higher than that at the outer edge. The maximum value of 24.71 kPa close to the inner edge of Wz may be used as the standard of complete ablation.

Guidelines and recommendations on the clinical use of shear wave elastography for evaluating thyroid nodule1.

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.

Evaluation of shear wave elastography for differential diagnosis of breast lesions: A new qualitative analysis versus conventional quantitative analysis.

OBJECTIVE: To evaluate a special kind of ultrasound (US) shear wave elastography for differential diagnosis of breast lesions, using a new qualitative analysis (i.e. the elasticity score in the travel time map) compared with conventional quantitative analysis. METHODS: From June 2014 to July 2015, 266 pathologically proven breast lesions were enrolled in this study. The maximum, mean, median, minimum, and standard deviation of shear wave speed (SWS) values (m/s) were assessed. The elasticity score, a new qualitative feature, was evaluated in the travel time map. The area under the receiver operating characteristic (AUROC) curves were plotted to evaluate the diagnostic performance of both qualitative and quantitative analyses for differentiation of breast lesions. RESULTS: Among all quantitative parameters, SWS-max showed the highest AUROC (0.805; 95% CI: 0.752, 0.851) compared with SWS-mean (0.786; 95% CI:0.732, 0.834; P = 0.094), SWS-median (0.775; 95% CI:0.720, 0.824; P = 0.046), SWS-min (0.675; 95% CI:0.615, 0.731; P = 0.000), and SWS-SD (0.768; 95% CI:0.712, 0.817; P = 0.074). The AUROC of qualitative analysis in this study obtained the best diagnostic performance (0.871; 95% CI: 0.825, 0.909, compared with the best parameter of SWS-max in quantitative analysis, P = 0.011). CONCLUSIONS: The new qualitative analysis of shear wave travel time showed the superior diagnostic performance in the differentiation of breast lesions in comparison with conventional quantitative analysis.

Complex cystic and solid breast lesions: Diagnostic performance of conventional ultrasound, strain imaging and point shear wave speed measurement.

OBJECTIVE: To assess the performance of conventional high frequency ultrasound (US) and US elastography in diagnosis of complex cystic and solid breast lesions. METHODS: Ninety three lesions in 93 patients underwent conventional US and US elastography, including strain elastography, acoustic radiation force impulse (ARFI) imaging, and point shear wave speed (SWS) measurement. RESULTS: Pathological examination revealed 31 (33.3%) of the 93 lesions were malignant and the remaining 62 (66.7%) were benign. Multivariate analysis showed that elder patient (OR: 25.301), internal vascularity (OR: 4.518), and not circumscribed margin (OR: 3.813) were independent predictors for malignancy, while predominately cystic lesions (OR: 0.178) was a predictor for benign lesions (all p < 0.05). Invalid SWS measurement was occurred in 19 of 31 (61.3%) malignant lesions and 16 of 62 (25.8%) benign lesions, respectively (p < 0.05). The mean SWS value for malignant lesions was significantly lower than that for benign ones, being 1.60±0.63 m/s (range, 0.68-2.70 m/s) versus 2.33±0.77 m/s (range, 0.67-3.97 m/s) (p < 0.05). Areas under the ROC curve (Azs) for Breast Imaging Reporting and Data System (BI-RADS) assessment, strain elasticity score, ARFI imaging and valid point SWS measurement were 0.844, 0.734, 0.763 and 0.778,respectively. CONCLUSIONS: US BI-RADS category, strain elastography score, ARFI imaging patterns and point SWS measurement are useful for malignancy prediction of complex cystic and solid breast lesions. The result that SWS for malignant lesions is lower than benign one should be carefully interpreted since invalid SWS measurement is excluded for analysis. The true stiffness of malignant cystic and solid lesions should be further evaluated with a new generation of two-dimensional SWS imaging.

Quality Measurement of Two-dimensional Shear Wave Speed Imaging for Breast Lesions: the Associated Factors and the Impact to Diagnostic Performance.

This study aimed to identify the associated factors for quality measurement (QM) of shear wave speed (SWS) imaging and to validate the additional value of QM in the diagnosis of breast lesions. From September 2014 to February 2015, conventional ultrasound and SWS imaging were performed in 338 women with 361 breast lesions. Binary logistic regression was used to identify associated factors for QM. Sensitivity, specificity and the area under receiver operating characteristic (ROC) curve (AUC) among maximum SWS (SWS max ), QM and SWS max plus QM (SWS max +QM) were compared to validate additional value of QM. Pathology confirmed 263 (72.9%) benign lesions and 98 (27.1%) malignancies. Maximum depth (Odds ratio [OR]: 1.398) and posterior features (OR: 1.206) were identified as independent associated factors for QM. Compared with SWS max and QM, the sensitivity of SWS max +QM increased from 67.3%, 64.3% to 83.7% whereas the specificity decreased from 90.5%, 72.6% to 65.4% (all P < 0.05). SWS max had the highest AUC in comparison with QM and SWS max +QM (0.849 vs. 0.685 vs. 0.745; P < 0.05). QM for breast lesions is associated with maximum depth and posterior features. Adding QM to SWS max is useful for breast cancer screening and SWS max alone is useful for breast cancer differentiation.

Thyroid imaging reporting and data system in assessment of cytological Bethesda Category III thyroid nodules.

OBJECTIVE: To assess the usefulness of thyroid imaging reporting and data system (TI-RADS) for cytological Bethesda Category III thyroid nodules (TNs). METHODS: This retrospective study included 121 patients with 121 TNs classified as Bethesda Category III at fine needle aspiration (FNA) cytology and thereafter underwent surgery. The TNs were classified according to US TI-RADS category and the malignancy risk of each category was calculated. RESULTS: Surgical pathology confirmed 43 (35.5%) malignant and 78 (64.5%) benign TNs. The malignancy risks of categories 3, 4a, 4b, 4c, and 5 TNs were 0%, 4.0%, 12.5%, 62.2%, and 100%, respectively. For those >10 mm (n = 55), the malignancy risks were 0%, 6.2%, 12.5%, 73.3%, and 100%, respectively, whereas for those ≤10 mm (n = 66), the risks were 0%, 0%, 12.5%, 56.7%, and 100%, respectively. CONCLUSION: Bethesda Category III TNs without suspicious US features or those ≤10 mm with only one suspicious US feature can be followed up with US.

Comparison of Virtual Touch Tissue Imaging & Quantification (VTIQ) and Virtual Touch Tissue Quantification (VTQ) for diagnosis of thyroid nodules.

OBJECTIVE: The aim of this study was to compare the diagnostic performance of Virtual Touch Tissue Imaging & Quantification (VTIQ) and Virtual Touch Tissue Quantification (VTQ) in differentiating benign from malignant thyroid nodules (TNs). MATERIALS AND METHODS: In this study 107 TNs in 107 patients were enrolled and analyzed. All of them were detected by conventional ultrasound (US) and confirmed by fine-needle aspiration (FNA) biopsy or surgery. VTIQ and VTQ examinations were performed on each nodule. Thereafter the median and mean of shear wave speed (SWS) values in lesions on VTIQ and VTQ were computed (SWS-median and SWS-mean). With cytological results of FNA and histological results adopted as the reference standard, area under the receiver operating characteristic (AUROC) curve analysis was performed to evaluate the diagnostic efficiency of VTIQ and VTQ in differentiation of TNs. RESULTS: Among the 107 lesions, 19 were papillary thyroid carcinomas (PTCs), 1 was medullary thyroid carcinoma (MTC) and 87 were benign. In total lesions, AUROC-median in VTIQ was significantly higher than that in VTQ (0.851 vs.0.759; p < 0.05). CONCLUSION: VTIQ and VTQ were equivalent in diagnosing TNs when using SWS-mean, whereas VTIQ showed better performance in comparison with VTQ when using SWS-median.

Shear wave speed imaging of breast lesions: Speed within the lesion, fat-to-lesion speed ratio, or gland-to-lesion speed ratio?

OBJECTIVE: To evaluate the diagnostic performance of shear wave speed (SWS) within the lesion, fat-to-lesion speed ratio (FLR), and gland-to-lesion speed ratio (GLR) for differentiation between benign and malignant breast lesions using a novel SWS imaging technique. METHODS: From April 2016 to June 2016, 182 breast lesions were prospectively included in the study. For each lesion, SWS-lesion, FLR, and GLR were calculated. Pathological results were used as the reference standard. Receiver operating characteristic curves (ROC) were plotted to assess the diagnostic performance. RESULTS: Of the 182 lesions, 142 (78.0%) were benign and 40 (22.0%) were malignant. Significant differences were found between benign and malignant lesions in SWS-lesion, FLR and GLR (2.12±0.64 m/s vs 3.87±1.45 m/s, 1.63±0.61 vs 2.60±1.04, and 1.33±0.39 vs 2.08±0.78, respectively. All P < 0.001). The optimal cut-off values of SWS-lesion, FLR, GLR were 2.88 m/s, 2.31 and 1.51, respectively. The diagnostic performance of SWS-lesion in terms of AUC was the highest (i.e. AUC = 0.845), in comparison with FLR and GLR alone or their combination. The associated sensitivity, specificity, and accuracy for SWS-lesion were 75.0%, 89.4%, and 86.3%, respectively. CONCLUSION: SWS-lesion is a valuable and sufficient method for differentiation between benign and malignant breast lesions.

A Risk Model based on Ultrasound, Ultrasound Elastography, and Histologic Parameters for Predicting Axillary Lymph Node Metastasis in Breast Invasive Ductal Carcinoma.

To develop a risk model for predicting axillary lymph node metastasis (LNM) in patients with breast invasive ductal carcinoma (IDCs) using ultrasound (US), US elastography of virtual touch tissue imaging (VTI) and virtual touch tissue imaging & quantification (VTIQ), and histologic parameters. This study included 162 breast IDCs in 162 patients. Univariate and multivariate analyses were used to identify the risk factors and a risk model was created. The results found that 64 (39.5%) of 162 patients had axillary LNMs. The risk score (RS) for axillary LNM was defined as following: RS = 1.3 × (if lesion size ≥20 mm) + 2.6 × (if taller than wide shape) + 2.2 × (if VTI score ≥5) + 3.9 × (if histological grade III) + 1.9 × (if positive C-erbB-2). The rating system was divided into 6 stages (i.e. Stage I, Stage II, Stage III, Stage IV, Stage V, and Stage VI) and the associated risk rates in terms of axillary LNM were 0% (0/19), 6.1% (2/33), 7.7% (3/39), 65.5% (19/29), 92.3% (24/26), and 100% (16/16), respectively. The risk model for axillary LNM established in the study may facilitate subsequent treatment planning and management in patients with breast IDCs.

Qualitative and quantitative analysis with a novel shear wave speed imaging for differential diagnosis of breast lesions.

To evaluate the diagnostic performance of a new two-dimensional shear wave speed (SWS) imaging (i.e. Toshiba shear wave elastography, T-SWE) in differential diagnosis of breast lesions. 225 pathologically confirmed breast lesions in 218 patients were subject to conventional ultrasound and T-SWE examinations. The mean, standard deviation and ratio of SWS values (m/s) and elastic modulus (KPa) on T-SWE were computed. Besides, the 2D elastic images were classified into four color patterns. The area under the receiver operating characteristic (AUROC) curve analysis was performed to evaluate the diagnostic performance of T-SWE in differentiation of breast lesions. Compared with other quantitative T-SWE parameters, mean value expressed in KPa had the highest AUROC value (AUROC = 0.943), with corresponding cut-off value of 36.1 KPa, sensitivity of 85.1%, specificity of 96.6%, accuracy of 94.2%, PPV of 87.0%, and NPV of 96.1%. The AUROC of qualitative color patterns in this study obtained the best performance (AUROC = 0.957), while the differences were not significant except for that of Eratio expressed in m/s (AUROC = 0.863) (P = 0.03). In summary, qualitative color patterns of T-SWE obtained the best performance in all parameters, while mean stiffness (36.05 KPa) provided the best diagnostic performance in the quantitative parameters.

The diagnostic performance of shear wave speed (SWS) imaging for thyroid nodules with elasticity modulus and SWS measurement.

To evaluate the diagnostic performance of a new technique of shear wave speed (SWS) imaging for the diagnosis of thyroid nodule with elasticity modulus and SWS measurement. 322 thyroid nodules in 322 patients (216 benign nodules, 106 malignant nodules) were included in this study. All the nodules received conventional ultrasound (US) and SWS imaging (Aplio500, Toshiba Medical Systems, Japan) before fine-needle aspiration (FNA) and/or surgery. The values of E-max and E-mean with elastic modulus (61.27 ± 36.31 kPa and 31.89 ± 19.11 kPa) or SWS (4.45 ± 1.49 m/s and 3.26 ± 2.71 m/s) in malignant nodules were significantly higher than those in benign lesions (29.18 ± 18.62 kPa and 15.85 ± 6.96 kPa, or 2.98 ± 0.85 m/s and 2.19 ± 0.42 m/s, all P < 0.001). No significant differences in area under the curve (AUC) between the SWS imaging parameters were found (all P > 0.05). In multivariate logistic regression analysis, E-max (m/s) with SWS was identified to be the strongest independent predictor for malignant nodules (odds ratio [OR] = 16.760), followed by poorly-defined margin (OR = 7.792), taller-than-wide shape (OR = 3.160), micro-calcification (OR = 2.422), and E-max (kPa) with elastic modulus (OR = 0.914). The AUC was 0.813 for E-max with SWS (m/s) and 0.796 for E-max with elastic modulus (kPa). With cut-off SWS value of 3.52 m/s in E-max, sensitivity of 69.8%, specificity of 81.5%, and accuracy of 77.6% were achieved. SWS imaging is a valuable tool in predicting thyroid malignancy. E-max with SWS measurement is the strongest independent predictor for thyroid malignancy.

Quality measurement on shear wave speed imaging: diagnostic value in differentiation of thyroid malignancy and the associated factors.

To evaluate the associated factors for quality measurement (QM) on shear wave speed (SWS) imaging and the additional value of QM for differentiation of thyroid nodules. A consecutive series of 238 patients with 254 thyroid nodules were enrolled. They were all evaluated by conventional ultrasound and SWS imaging and were finally proven pathologically. QM was used to assess whether SWS propagation was authentic and was classified as high QM and Low QM. Twelve variables were analyzed to evaluate the associated factors for QM using binary logistic regression. Receiver operating characteristic (ROC) curve was plotted on SWS and SWS+QM. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), accuracy and area under ROC curve (AUC) were calculated. The study included 170 benign thyroid nodules (160 high QM and 10 low QM) and 84 malignant thyroid nodules (56 high QM and 28 low QM) (P < 0.001). The mean SWS of benign and malignant nodules were 2.51 ± 0.47 m/s and 3.43 ± 1.21 m/s respectively (P < 0.001). The sensitivities, specificities, PPVs, NPVs, accuracies and AUCs were 77.4%, 80.0%, 65.7%, 87.7%, 79.1%, 0.82 for SWS alone with SWS ≥ 2.78 m/s; 33.3-34.5%, 91.2-94.1%, 65.9-73.7%, 73.8-74.1%, 72.4-74.0%, 0.63-0.64 for QM alone and 84.5-85.7%, 72.4-75.9%, 60.5-63.4%, 90.8-91.0%, 76.8-78.7%, 0.79-0.80 for SWS+QM. Nodule depth was identified to be the strongest associated factor for QM of SWS, followed by malignancy and SWS. In conclusion, QM for thyroid nodule is associated with nodule depth, malignancy, and SWS. QM improves the specificity in comparison with SWS alone, whereas SWS+QM does not improve the overall diagnostic performance.