Shear wave elastography versus real-time elastography on evaluation thyroid nodules: a preliminary study

Accuracy of Ultrasound Diagnosis of Benign and Malignant Thyroid Nodules: A Systematic Review and Meta-Analysis

Background

Distinguishing between benign and malignant thyroid nodules remains difficult. Ultrasound has been established as a non-invasive and relatively simple imaging technique for thyroid nodules. This study aimed to assess the diagnostic accuracy of conventional ultrasound and ultrasound elastography for the differentiation between benign and malignant thyroid nodules by meta-analyzing published studies.

Methods

Literature was retrieved from the PubMed and Embase databases from inception to May 31, 2022. The literature was screened using inclusion and exclusion criteria. The Quality Assessment of Diagnostic Accuracy Studies (QUADAS2) scale was used to assess the quality of the included literature. Publication bias of the included studies was assessed by Deek's funnel plot. Heterogeneity tests were performed using Cochrane Q statistic and I2 statistic.

Results

Finally, 9 articles were included. The meta-analysis showed that the combined sensitivity and specificity of ultrasound for the diagnosis of thyroid nodules were 0.88 [95% CI (0.83-0.91)] and 0.86 [95% CI (0.79-0.90)], respectively. The area under the curve (AUC) of the summary receiver operating characteristic curve (SROC) was 0.92 [95% CI (0.90-0.94)]. There was no significant publication bias in this study. Discussion. Existing evidence shows that ultrasound has a certain accuracy in diagnosing benign and malignant thyroid nodules, providing a scientific basis for thyroid assessment and diagnosis.

Comparing shear wave elastography and fine needle aspiration in the diagnosis of solid thyroid nodules

This descriptive study was performed on individuals who were referred to Imam Reza Hospital for fine needle aspiration biopsy (FNAB) based on the results of gray scale ultrasound and the decision of the referring physician. In addition to determining the gray scale characteristics of the nodules, shear wave elastography (SWE) was also performed and the results were recorded. These were also taken from the patients FNAB results. Finally, the findings of SWE and FNAB methods were compared and analyzed using SPSS software version 16. Based on the results presented herein, a significant relationship was observed between the results of SWE and FNA in the diagnosis of malignancy in solid thyroid nodules. This agreement was found to be higher in men (K = 0.866) than women (K = 0.849). Taken together, our data suggest that shear wave elastography can replace FNA in the diagnosis of malignancy in solid thyroid nodules.

SuperSonic shear imaging for the differentiation between benign and malignant thyroid nodules: a meta-analysis

PURPOSE

To assess the diagnostic value of SuperSonic shear imaging (SSI) for the differentiation between benign and malignant thyroid nodules through meta-analysis.

METHODS

Online database searches were performed on PubMed, EMBASE, the Cochrane Library, and the Web of Science until 31 July 2021. The Quality Assessment of Diagnostic Accuracy Studies-2 tool was used to assess the quality of the included studies. Three measures of diagnostic test performance were used to examine the value of SSI, including the summary area under the receiver operating characteristic curve (AUROC), the summary diagnostic odds ratio (DOR), and the summary sensitivity and specificity. Heterogeneity was explored using meta-regression and subgroup analyses.

RESULTS

Finally, 21 studies with 3376 patients were included in this study. There were a total of 4296 thyroid nodules, in which 1806 malignant nodules and 2490 benign ones were involved. Thyroid nodules exhibited a malignancy rate of 42.0% (range 5.6-79.8%), 95.1% of which were of papillary variant. SSI showed a summary sensitivity of 74% [95% confidence interval (CI) 67-79%], specificity of 82% (95% CI 77-87%) and AUROC of 0.85 (95% CI 0.82-0.88) for the differentiation between benign and malignant thyroid nodules. The summary positive likelihood ratio (LR), negative LR, and DOR were 4.2 (95% CI 3.3-5.3), 0.32 (95% CI 0.26-0.40), and 13 (95% CI 9-18), respectively.

CONCLUSIONS

SSI showed high accuracy in the diagnostic differentiation between benign and malignant thyroid nodules and can be served as a noninvasive and important adjunct for thyroid nodule evaluation.

US-Elastography With Different Techniques for Thyroid Nodule Characterization: Systematic Review and Meta-analysis

Background

Thyroid nodules are frequent in adult population and thyroid cancer incidence has increased dramatically over the past three decades. The aim of this systematic review and meta-analysis was to evaluate the US-Elastosonography (USE) diagnostic performance in assessing the thyroid nodules malignancy risk.

Methods

PubMed and Embase databases were searched from January 2011 to July 2021. We extracted data from selected studies and calculated the overall diagnostic accuracy of qualitative USE, semi-quantitative USE and quantitative USE. Summary receiver operating characteristic (ROC) curve was elaborated to show the results. All statistical tests were performed using Metadisc and Medcal software package.

Results

Finally 72 studies with 13,505 patients and 14,015 thyroid nodules (33% malignant) undergoing elastography were included. The pooled sensitivity, specificity and AUC were 84%, 81%, and 0.89 respectively for qualitative USE; 83%, 80%, and 0.93 for semi-quantitative USE and 78%, 81% and 0.87, for quantitative USE. The qualitative and semiquantitative USE present very similar diagnostic accuracy values and both better than the quantitative USE.

Conclusions

USE is a useful imaging tool for thyroid nodule characterization. In accordance with recent guidelines and meta-analyses, the USE could be used daily in thyroid nodule malignancy risk stratification.

Systematic Review Registration

PROSPERO: CRD42021279257.

Application value of gray-scale ultrasound and shear wave elastography in differential diagnosis of thyroid nodules

BACKGROUND

The global prevalence of thyroid cancer has increased significantly in recent years. Ultrasonography is the preferred method for differentiating benign and malignant thyroid nodules preoperatively and is recommended by guidelines.

OBJECTIVE

To assess the application value of gray-scale ultrasound and shear wave elastography in distinguishing small thyroid nodules.

METHODS

A retrospective analysis of 228 thyroid nodules, all of which were confirmed by pathology after surgery or FNA from January 2019 to January 2020, was carried out. All nodules were divided into a ⩽ 5 mm group and a > 5 mm group according to their maximum size. We compared the differences in the gray scale and elastography of the nodules between the two groups and the accuracy of different diagnostic methods.

RESULTS

The accuracies of gray-scale ultrasound and shear wave elastography in the ⩽ 5 mm group were found to be lower than those in the > 5 mm group, and the gray-scale accuracy was slightly higher than that of shear wave elastography in both groups (p< 0.05). The largest AUC (area under the curve) of elastic parameters in the ⩽ 5 mm and > 5 mm groups was found for Emax and Esd, respectively. Based on a combination of these two parameters, the accuracies of the two groups were significantly higher than those of the parameters or gray scale alone (p< 0.05) and were 84.62% and 85.48%, respectively.

CONCLUSION

Shear wave elastography is valuable in the diagnosis of benign and malignant thyroid nodules using ultrasonography. When combining gray-scale ultrasound and shear wave elastography, the diagnostic accuracy is obviously improved, especially for ⩽ 5 mm small thyroid nodules.

Elastography and Doppler May Bring a New Perspective to TIRADS, Altering Conventional Ultrasonography Dominance

RATIONALE AND OBJECTIVES

The main aim of ultrasonography (US) examining thyroid nodules is to differentiate malignant nodules from benign nodules. Several professional societies and groups of investigators have defined guidelines such as Thyroid Imaging Reporting and Data System (TIRADS) to provide the standardized language and approach to thyroid nodules. This study is aimed to investigate the compatibility of such classification systems with the pathological diagnosis of nodules and evaluate the contribution of the Shear-wave elastography (SWE) and Doppler ultrasonography (DUS) findings.

MATERIALS AND METHODS

This is a prospective study. Patients with thyroid US exams between December 2017 and April 2019 were included. In the study, eligible 210 nodules from 210 patients were enrolled. For stratification, the conventional B-mode US, SWE and DUS were performed. According to Kwak, American College of Radiology (ACR), and European (EU)-TIRADS, Nodules were classified separately, and a new scoring system whose the criteria was put defined in the study has developed.

RESULTS

For SWE; Emean cut-off value was 33 kPa with a sensitivity and specificity of 95,6% (95% CI: 0,85-0,98) and 95% (95% CI:0,90-0,97) respectively (p <0.001). For spectral DUS; resistivity index (RI) cut-off value was 0.64 with a sensitivity and specificity of 73,3% (95% CI:0,59-0,83) and 80% (95% CI:0,73-0,85) respectively (p <0.001). Kwak TIRADS, American College of Radiology TIRADS, EU-TIRADS, and new system were compared by ROC curve analysis. The new system has the highest sensitivity, specificity, PPV, NPV, accuracy, and AUC compared to others.

CONCLUSIONS

The new scoring system has shown that SWE and DUS findings may alter the categorization in TIRADS and increase sensitivity and specificity.

Is Diagnostic Performance of Quantitative 2D-Shear Wave Elastography Optimal for Clinical Classification of Benign and Malignant Thyroid Nodules?: A Systematic Review and Meta-analysis

RATIONALE AND OBJECTIVE

This study is a dedicated 2D-shear wave elastography (2D-SWE) review aimed at systematically eliciting up-to-date evidence of its clinical value in differential diagnosis of benign and malignant thyroid nodules.

METHODS

PubMed, Web of Science, and Scopus databases were searched for studies assessing the diagnostic value of 2D-SWE for thyroid malignancy risk stratification published until December 2016. The retrieved titles and abstracts were screened and evaluated according to the predefined inclusion and exclusion criteria. Methodological quality of the studies was assessed using the Quality Assessment of Studies of Diagnostic Accuracy included in Systematic Review 2 (QUADAS-2) tool. Extracted 2D-SWE diagnostic performance data were meta-analyzed to assess the summary sensitivity, specificity, and area under the receiver operating characteristic curve.

RESULTS

After stepwise review, 14 studies in which 2D-SWE was used to evaluate 2851 thyroid nodules (1092 malignant, 1759 benign) from 2139 patients were selected for the current study. Study quality on QUADAS-2 assessment was moderate to high. The summary sensitivity, specificity and area under the receiver operating characteristic curve of 2D-SWE for differential diagnosis of benign and malignant thyroid nodules were 0.66 (95% confidence interval [CI]: 0.64-0.69), 0.78 (CI: 0.76-0.80), and 0.851 (Q* = 0.85), respectively. The pooled diagnostic odds ratio, negative likelihood ratio, and positive likelihood ratio were 12.73 (CI: 8.80-18.43), 0.31 (CI: 0.22-0.44), and 3.87 (CI: 2.83-5.29), respectively.

CONCLUSION

Diagnostic performance of quantitative 2D-SWE for malignancy risk stratification of thyroid nodules is suboptimal with mediocre sensitivity and specificity, contrary to earlier reports of excellence.

Conventional ultrasound, color Doppler, TI-RADS, and shear wave elastography for thyroid nodule differentiation: a study of efficacy compared with the histopathology results

Background

Although a minority of the thyroid nodules is malignant, usually the invasive diagnostic procedures are warranted. This prospective study aims to assess the diagnostic performance of the US criteria in addition to the TI-RADS score and the SWE for the differentiation between the benign and malignant thyroid nodules as a potential surrogate for the invasive procedures.

Results

Ninety-nine patients with thyroid nodules (79 females and 20 males, with a mean age of 45.9 ± 7.7 years; 30–69 years) were enrolled in this study and underwent conventional ultrasound, color Doppler, TI-RADS scoring, and shear wave elastography (SWE); the findings were correlated to the histopathological results.

Our results revealed a significant increase in SWE elasticity indices (EIs) and presence of color Doppler signals in malignant nodules as compared with the benign ones (ρ < 0.05). Combined TI-RADS and SWE as well as TI-RADS and color Doppler imaging had given a better sensitivity for detection of malignancy.

Conclusion

Elasticity indices had shown a significantly high diagnostic performance that is almost approaching the histopathological results. Combined SWE, color Doppler and TI-RADS, as a sum of findings, could effectively differentiate between benign and malignant thyroid nodules. Furthermore, it had offered a non-invasive tool for accurate risk stratification of malignant nodules.

Systematic review and meta-analysis of ultrasonic elastography in the diagnosis of benign and malignant thyroid nodules

Background

In recent years, ultrasound elastography (USE) has been the main diagnostic technique for benign and malignant thyroid nodules. However, it cannot display the blood flow signals of nodules with smaller diameters clearly, which decreases its diagnostic accuracy.

Methods

Chinese and English databases were searched using "ultrasonic elastography", "benign and malignant thyroid nodules", and "diagnose" as the search terms. RevMan 5.3 software was used for meta-analysis.

Results

A total of 11 randomized controlled trials (RCTs) were included. Eight articles analyzed clinical symptoms, and the heterogeneity test results were Chi² =7.46, df=7, I²=6%, and P=0.38; and Z=11.44, OR =14.58, 95% confidential interval (CI): 9.21-23.07, and P<0.01. The diagnostic efficacy of USE was analyzed in 8 articles, and the heterogeneity test results were Chi² =3.03, df=7, I²=0%, and P=0.88; and Z=6.33, OR =7.47, 95% CI: 4.01-13.93, and P<0.01. The pathological diagnosis results of randomized controlled trials were analyzed in 10 literatures, and the heterogeneity test results were Tau² =0.78, Chi² =20.97, df=9, I²=57%, and P=0.01; and Z=7.27, OR =14.67, 95% CI: 7.11-30.27, and P<0.01. After meta-analysis, the combined sensitivity was 72.26% (95% CI: 0.625-0.764) and the combined specificity was 95.35% (95% CI: 0.815-0.943). The area under the receiver operating characteristic curve (AUC) was 0.857.

Conclusions

This meta-analysis confirmed that USE shows high sensitivity and specificity in diagnosing benign and malignant thyroid nodules, which could reduce the false negative rate (FNR) and false positive rate (FPR), showing high clinical diagnostic value.

Accuracy of shear wave elastography in characterization of thyroid nodules in children and adolescents

BACKGROUND

Thyroid nodules are an important health problem in children and adolescents. They possess a higher risk of malignancy in comparison to adults. This fact forms a great dilemma for clinicians. The aim of this study was to evaluate the reliability of shear wave elastography (SWE) as a non-invasive technique in the characterization of thyroid nodules in children and adolescents.

METHODS

This prospective study included 56 patients with thyroid nodules. All the patients underwent clinical assessment, laboratory investigations, ultrasound, and Doppler examination, followed by an SWE assessment. Statistical analysis was performed and the best cut-off value to differentiate benign from malignant nodules was determined using the ROC curve and AUC.

RESULTS

Seventy-two nodules were detected in the examined patients (ages ranged from 11 to 19 years, with mean age of 14.89 ± 2.3 years). Fifty-eight nodules (80.6%) were benign, and fourteen nodules (19.4%) were malignant (histopathologically proved). Highly suspicious criteria for prediction of malignancy by ultrasound and Doppler were hypoechoic echopattern, internal or internal and peripheral vascularity, microcalcifications, taller-than-wide dimensions, irregular outlines, and absence of halo (p < 0.05). The diagnostic performance for their summation was 70.69% sensitivity, 82.8% specificity, 80.45% accuracy, a 63.79% positive predictive value (PPV), and 87.9% negative predictive values (NPV). Regarding SWE, our results showed that 42.2 kPa was the best cut-off value, with AUC = 0.921 to differentiate malignant from benign nodules; the diagnostic performance was 85.71% sensitivity, 94.83% specificity, 93.06% accuracy, 76.9% PPV, and 93.2% NPV.

CONCLUSION

Shear wave elastography is a non-invasive technique that can assist in the diagnosis of malignant thyroid nodules among children and adolescents.

Comparison of 2 shear wave elastography systems in reproducibility and accuracy using an elasticity phantom

This study aimed to compare the accuracy and inter- and intra-observer reproducibility of the measured elasticity between 2 shear wave elastography systems. Three breast radiologists examined 8 targets of 4 different levels of stiffness (size: 11 mm, 4 mm) in an elasticity phantom (Customized 049A Elasticity QA Phantom, CIRS, Norfolk, VA, USA) using 2 different shear wave ultrasound elastography systems: SuperSonic Imagine (SSI) (SSI, Aix en Provence, France) and ShearScan (RS-80A, Samsung Medison, Seoul, Korea). Three radiologists performed ultrasound (US) elastography examinations for the phantom lesions using 2 equipment over a 1-week interval. Intra- and inter-observer reproducibility and the accuracy of the measured elasticity were analyzed and compared between the 2 systems. The accuracy of shape was also analyzed by shape-matching between B-mode and elastography color image. Intra-class correlation coefficients (ICC) were used in statistical analysis. For measured elasticity, the intra-observer and inter-observer reproducibility were excellent in both SSI and ShearScan (0.994 and 0.998). The overall accuracy was excellent in both systems, but the accuracy in small lesions (4 mm target) was lower in SSI than ShearScan (0.780 vs 0.967). The accuracy of shape-matching on the elastography image was 59.0% and 81.4% in the SSI and ShearScan, respectively. In conclusion, the SSI and ShearScan showed excellent intra- and inter-observer reproducibility. The accuracy of the Young's modulus was high in both the SSI and ShearScan, but the SSI showed decreased accuracy in measurement of elasticity in small targets and poor shape-matching between the B-mode image and color-coded elastography image.

Transthoracic ultrasound shear wave elastography for the study of subpleural lung lesions

PURPOSE

The aim of this study was to assess whether new-generation shear wave elastography (SWE) is suitable for the characterization of lung subpleural lesions.

METHODS

In total, 190 consecutive patients with subpleural lung lesions received ultrasonography and SWE. Patients with suspected malignancy underwent ultrasound-guided transthoracic needle biopsy. Final diagnoses were made on the basis of patients' clinical course, microbiological studies, and histological results. SWE was also performed in 25 healthy volunteers.

RESULTS

We found no statistically significant differences in stiffness between lung carcinomas, lung metastases, and pneumonia (P=0.296) or between different histological types of lung cancer (P=0.393). Necrosis was associated with reduced stiffness in pneumonia. Excluding necrotic lesions, pneumonia showed higher stiffness than lung carcinomas (2.95±0.68 m/s vs. 2.60±0.54 m/s, P=0.006). Chronic pneumonia showed increased stiffness (3.03±0.63 m/s), probably due to the presence of fibrotic tissue on histology. Pleural effusion was associated with a statistically significant reduction in stiffness, both in lung carcinomas (P=0.004) and lung metastases (P=0.002). The presence of air in healthy lung tissue may lead to incorrect speed estimates due to shear wave reflection (very high values, 14.64±2.19 m/s).

CONCLUSION

Transthoracic SWE could not distinguish lung malignancy from pneumonia, or between different histological types of lung carcinomas. In particular, SWE seems unable to resolve the clinical dilemma of chronic subpleural consolidations.

Shear Wave Elastography Combined with Thyroid Imaging Report and Data System for Risk Stratification of Thyroid Nodule Malignant Tumor

Benign and malignant thyroid cancer diagnosis is crucial. Our study intends to evaluate the role of shear wave elastography (SWE) and thyroid imaging report and data system (TI-RADS) in diagnosing the benign and malignant thyroid nodules. 100 thyroid nodules patients were recruited and evaluated by SWE and TI-RADS before fine needle biopsy and/or surgery. The maximum elastic index (Emax), mean elasticity index of thyroid nodules (Emean), minimum elastic index (Emin) and elastic ratio (ER) was measured and compared between different imaging. Ultrasound diagnosis showed solid nodules with significant hypoechoic, unclear boundary, and microcalcification. TI-RADS value was measured based on suspected ultrasound features. Combination of SWE and TI-RADS was performed. Among the 100 nodules, 38 were benign (38.0%), 62 were malignant (62.0%), and malignant nodules had significantly elevated SWE and TI-RADS compared with benign nodules (P < 0.001). The optimal SWE threshold for Emax was 51.95 kPa, with a sensitivity of 81.44% and specificity of 83.19%. There were two methods for combining SWE and TI-RADS. One was sequential detection, with a specificity of 95.80%, positive similarity ratio of 18.16 and PPV of 96.73%; the other was parallel detection method with a sensitivity of 94.85%, negative similarity ratio of 0.07 and PPV of 90.00%. Our results suggest that combination of SWE and TI-RADS might be applied to identify benign and malignant thyroid cancers.

Evaluation of thyroid micro-carcinoma using shear wave elastography: Initial experience with qualitative and quantitative analysis

PURPOSE

We aimed to assess the diagnostic performance of shear wave elastography (SWE) to assess perinodular stiffness before fine needle aspiration (FNA) of thyroid nodules with a maximum diameter of 1.0 cm.

METHOD

This retrospective study included 69 thyroid nodules in 68 patients who underwent conventional ultrasound and SWE before ultrasound-guided FNA or surgical excision. The stiffness of perinodular regions was evaluated using wave patterns. Quantitative SWE features were also assessed. Sensitivity, specificity, accuracy, and area under the receiver operating characteristic curve were calculated using conventional ultrasound and conventional ultrasound with SWE.

RESULTS

Of the 69 nodules, 57(82.6 %)were malignant and 12(17.4 %)were benign. The maximum elastic modulus (Emax) was higher for malignant nodules(P＜ 0.05). There was no significant difference in mean elastic modulus or minimum elastic modulus between malignant and benign nodules. The Emax≥ 28.2 kPa was the best cut-off value for malignant base on receiver operating curve. Perinodular stiffness was significantly greater for malignant nodules compared with benign nodules according to shear wave patterns. Compared with ultrasound alone, the rate of benign lesions recommended for FNA decreased from 75.0 % (9/12) to 25.0 % (3/12) with conventional ultrasound plus SWE.

CONCLUSION

SWE provides quantitative and qualitative information when used with conventional ultrasound. SWE has the potential to reduce the number of unnecessary FNA procedures.

Shear-wave elastography in thyroid ultrasound: Can be a predictor of extrathyroidal extension and cervical lymph node metastasis in papillary thyroid carcinoma?

ABSTRACT

This study aimed to investigate whether extrathyroidal extension (ETE) and cervical lymph node metastasis (LNM) can be predicted using elasticity parameters of shear-wave elastography (SWE) combined with B-mode ultrasound (US) of papillary thyroid carcinomas (PTCs).We retrospectively reviewed 111 patients who underwent preoperative SWE evaluation among PTC patients from July 1, 2016 to June 20, 2018. Patients were divided into 2 groups based on the presence or absence of ETE based on pathology reports. Univariate and multivariate analyses of clinical and radiologic features including B-mode US features, US patterns, and SWE parameters were performed. These analyses were repeated in LNM positive and negative groups. The diagnostic performance of SWE parameters were also evaluated.Of the 111 patients, 33 had ETE, 78 did not have ETE, 44 had LNM, and 67 did not have LNM. A taller-than-wide shape and T3 stage on US were associated with ETE. Female sex, total thyroidectomy, and T3 stage on US were associated with LNM. When B-mode US and SWE were combined, there was no improvement in diagnostic performance.Combination of SWE and B-mode US findings is not useful for predicting ETE and LNM status in PTC patients.

Diagnostic Accuracy Evaluation of Two-Dimensional Shear Wave Elastography in the Differentiation Between Benign and Malignant Thyroid Nodules: Systematic Review and Meta-analysis

OBJECTIVES

To evaluate two-dimensional (2D) shear wave elastography (SWE) performance as an independent predictor of malignancy in the diagnostic differentiation of thyroid nodules (TNs), including subgroup analyses of different manufacturers and respective cutoffs points.

METHODS

The online databases MEDLINE (PubMed), Embase, and the Cochrane Library were searched for articles using 2D SWE in TN evaluation. After good-quality relevant thyroid-specific articles were selected, the main data, plus their sensitivity and specificity, were tabulated. Summary receiver operating characteristic curves were generated to verify the accuracy of data obtained from 3 manufactures. A meta-analysis was performed to evaluate whether clinical recommendations can be improved by the use of 2D SWE to differentiate TNs.

RESULTS

The sensitivity and specificity parameters of 2D SWE for the differentiation between benign and malignant TNs according to different instruments were, respectively, as follows: Toshiba SWE (Toshiba Medical Systems, Tochigi, Japan), 0.77 (95% confidence interval [CI], 0.70-0.83) and 0.76 (95% CI, 0.72-0.81); Virtual Touch tissue imaging and quantification (Siemens Medical Solutions, Mountain View, CA), 0.72 (95% CI, 0.67-0.77) and 0.81 (95% CI, 0.78-0.84); and SuperSonic SWE (SuperSonic Imagine, Aix-en-Provence, France), 0.63 (95% CI, 0.59-0.66) and 0.81 (95% CI, 0.79-0.83). The summary receiver operating characteristic curves showed the following area under the curve syntheses: Toshiba SWE, 0.84 (Q* = 0.7707); Virtual Touch tissue imaging and quantification, 0.85 (Q* = 0.7809); and SuperSonic SWE, 0.88 (Q* = 0.8102). Positive and negative predictive values varied, respectively, from 16% to 94% and 29% to 100%, considering all included articles. The overall accuracy ranged from 53% to 93%.

CONCLUSIONS

Two-dimensional SWE is a relevant and an important tool that supports ultrasound in clinical practice in the diagnostic differentiation between benign and malignant TNs.

Added value of circulating miRNA expression profiling to sonographic TI-RADS classification in the diagnosis of thyroid nodules

Potential use of sonographic TI-RADS classification combined with circulating miRNA expression profiling in the diagnosis of thyroid nodules was explored. Retrospective analysis was performed on clinical data of 121 patients with thyroid nodules. The biopsy specimens of patients obtained through ultrasound-guided aspiration and blood specimens were evaluated in Zhengzhou Central Hospital Affiliated to Zhengzhou University from June 2018 to June 2019. In addition, the blood specimen test results of 121 healthy volunteers (control group) who underwent physical examination were retrospectively analyzed. Results of sonographic TI-RADS classification and circulating miRNA expression profiling were compared with the pathological results. Of the 212 nodules, 2 fell into TI-RADS category 2 and were diagnosed as benign. Malignant nodules accounted for 4.35, 37.14, 84.78, 93.33 and 96.77% of those nodules that fell into TI-RADS categories 3, 4a, 4b, 4c and 5, respectively. Of the 121 patients, 92.55% had with nodular goiter, 3.31% had inflammatory nodules, 2.48% toxic nodular goiter, 0.83% thyroid cysts and 0.83% thyroid tumors. A nodule that fell into a higher TI-RADS classification category had a higher risk of malignancy. The expression levels of miRNA146b, miRNA187, miRNA375, miRNA-222-3p and miRNA-151a-5p were higher, while the level of miRNA138 was lower, in patients with either benign or malignant thyroid nodules compaed to those in the control group. The expression levels of miRNA146b, miRNA187, miRNA375, miRNA-222-3p and miRNA-151a-5p were higher, while the level of miRNA138 was lower, in patients with malignant thyroid nodules than those in patients with benign thyroid nodule (P<0.05). The AUC of the combined diagnostic method was 0.973, which was significantly different from the AUCs of the individual diagnostic method (P<0.05). In conclusion, sonographic TI-RADS classification combined with circulating miRNA expression profiling can improve the diagnosis of thyroid nodules.

Diagnostic Performance of a Combination of Shear Wave Elastography and B-Mode Ultrasonography in Differentiating Benign From Malignant Thyroid Nodules

Objectives

This study was conducted to compare clinicopathologic and radiologic factors between benign and malignant thyroid nodules and to evaluate the diagnostic performance of shear wave elastography (SWE) combined with B-mode ultrasonography (US) in differentiating malignant from benign thyroid nodules.

Methods

This retrospective study included 92 consecutive patients with 95 thyroid nodules examined on B-mode US and SWE before US-guided fine-needle aspiration biopsy or surgical excision. B-mode US findings (composition, echogenicity, margin, shape, and calcification) and SWE elasticity parameters (maximum [E_max], mean, minimum, and nodule-to-normal parenchymal ratio of elasticity) were reviewed and compared between benign and malignant thyroid nodules. The diagnostic performance of B-mode US and SWE for predicting malignant thyroid nodules was analyzed. The optimal cutoff values of elasticity parameters for identifying malignancy were determined. Diagnostic performance was compared between B-mode US only, SWE only, and the combination of B-mode US with SWE.

Results

On multivariate logistic regression analysis, age (odds ratio [OR], 0.90; P=0.028), a taller-than-wide shape (OR, 11.3; P=0.040), the presence of calcifications (OR, 15.0; P=0.021), and E_max (OR, 1.22; P=0.021) were independent predictors of malignancy in thyroid nodules. The combined use of B-mode US findings and SWE yielded improvements in sensitivity, the positive predictive value, the negative predictive value, and accuracy compared with the use of B-mode US findings only, but with no statistical significance.

Conclusion

When SWE was combined with B-mode US, the diagnostic performance was better than when only B-mode US was used, although the difference was not statistically significant.

The values of shear wave elastography in avoiding repeat fine-needle aspiration for thyroid nodules with nondiagnostic and undetermined cytology

OBJECTIVE

To evaluate the value of shear wave elastography (SWE) in avoiding repeat fine-needle aspiration of thyroid nodules with nondiagnostic and undetermined cytology.

METHODS

A total of 232 thyroid nodules with nondiagnostic (n = 132) and undetermined (n = 100) cytology underwent ultrasound (US) and SWE, followed by repeat ultrasound (US)-guided fine-needle aspiration cytology (FNAC). The final diagnosis was based on cytological or pathological findings. The US and SWE characteristics of benign and malignant nodules were compared using the χ² -test. The receiver operating characteristic (ROC) curves of the thyroid imaging reporting and data system (TI-RADS) categories from the US and the E_Mean and E_SD from the SWE were graphed, and the areas under the curves (AUCs) were compared using a Z test.

RESULTS

There were significant differences between the benign and malignant nodules in terms of the echogenicity, shape, margin, calcification and TI-RADS categories (all P < 0.05). The differences were significant between the malignant and benign nodules for E_Mean [(34.57 ± 14.81) kPa vs. (19.18 ± 7.09) kPa] and E_SD [(13.68 ± 13.01) kPa vs. (3.97 ± 2.58) kPa] (both P < 0.001). Though the difference in the AUCs of E_Mean (0.864) and E_SD (0.876) was not significant (P = 0.745), they both had higher diagnostic performances in comparison with TI-RADS categories (0.762) (all P < 0.05). Moreover, E_SD attained a sensitivity of 100% with a relatively higher specificity of 49.75% when its cut-off value was 3.3 kPa.

CONCLUSIONS

Shear wave elastography is a promising imaging method for reducing repeat FNAC for benign thyroid nodules with nondiagnostic and undetermined cytology when using E_SD as an index.

The Value of Elasticity Contrast Index in the Differential Diagnosis of Thyroid Solid Nodules

OBJECTIVES

To assess the clinical value of elasticity contrast index (ECI) in differentiating malignant thyroid nodules from benign ones.

METHODS

Conventional ultrasound and elastography with pulsation of the carotid artery used as the compression source were retrospectively reviewed on 175 patients (143 females and 32 males; mean ± SD age, 45.17 ± 11.45 years) with 236 solid nodules (113 malignant and 123 benign). All nodules were confirmed by fine-needle aspiration or surgery to be accurately diagnosed. Elasticity contrast index values were computed and used to quantify local stiffness contrast within a nodule as determined with elastography. Elasticity contrast index values between the malignant and benign groups were compared and then related with pathological results. Diagnostic performance of this method was evaluated with use of the receiver operating characteristic curve.

RESULTS

Mean ± SD ECI values for malignant thyroid nodules were significantly greater than those for benign nodules (3.67 ± 1.20 vs 1.80 ± 0.74, P < 0.01). Area under the receiver operating characteristic curve of ECI values was 0.907 (95% confidence interval, 0.867-0.948), and the best cutoff point was 2.16, leading to a sensitivity of 90.3%, specificity of 82.9%, positive predictive value of 83.7% and negative predictive value of 91.2%.

CONCLUSIONS

Elasticity contrast index values can serve as a useful parameter in the differential diagnosis of solid thyroid nodules. With the use of ECI values, objective quantitative information on the tumor stiffness can be achieved to improve diagnostic confidence.

Multifactor Analysis of Thyroid Stiffness in Graves Disease: A Preliminary Study

OBJECTIVE. The aim of this study was to evaluate the value of shear wave elastography (SWE) in Graves disease (GD) and to identify the potential factors influencing thyroid stiffness. MATERIALS AND METHODS. A total of 207 subjects were enrolled and underwent SWE examination in the study, including 162 patients with GD and 45 healthy volunteers with normal thyroids, matched for age and sex. For all subjects, five measurements of elastic modulus values (SWE mean, SWE minimum, and SWE maximum of a 9-mm ROI) were performed on each thyroid lobe, and a mean value was calculated. The indicators including free three-triiodothyronine (FT₃), free thyroxine (FT₄), thyroid-stimulating hormone (TSH), thyroid size, isthmus thickness, anti-thyroid peroxidase (TPO) antibodies (Abs), and antithyroglobulin (TG) Abs were detected in the 162 patients with GD, among whom 88 patients underwent initial TSH receptor (TR) Ab examination. RESULTS. The elastic modulus values for patient with GD were significantly higher than those for healthy control subjects. The ROC AUC values for GD by SWE mean was 0.656, and the cutoff value was 15.45 kPa. The sensitivity and specificity were 56.8% and 71.1%, respectively. The duration of disease, thyroid size, isthmus thickness, and levels of TPO Ab, TG Ab, and TR Ab were positively correlated with SWE mean in GD. However, there was no correlation between age, FT₃, FT₄, TSH, and SWE mean. CONCLUSION. Quantitative SWE helps in the diagnosis of GD. The duration of disease, thyroid size, isthmus thickness, and levels of thyroid autoantibodies (TPO Ab, TG Ab, and TR Ab) could influence thyroid stiffness of GD.

Comparing the Sensitivity and Specificity of Two-Dimensional Shear Wave Elastography and Fine Needle Aspiration in Determining Malignant Thyroid Nodules

Background

Malignancy in thyroid nodules is a common clinical problem, and epidemiological studies have shown that it is increasing. Since malignancy is a very important problem in treating patients and misdiagnosis leads to many physical and financial damages, the importance of diagnostic methods becomes more important. Hence, the aim of this study was to investigate the sensitivity and specificity of the two dimensional-shear wave elastography (2D-SWE) diagnostic method in comparison with fine-needle aspiration (FNA) in determining the malignant thyroid nodules.

Materials and Methods

This study is cross-sectional which was performed on 57 thyroid nodules are proven by conventional ultrasound. Afterward, 2D-SWE images were taken with the help of a superSonic ultrasound machine. Then, FNA was performed from the thyroid nodules and the specimens were evaluated in a single specialized thyroid pathology center. The results of conventional sonography and 2D-SWE were compared with histopathologic results as a gold standard method. The elasticity quantity was recorded by measuring the amount of the appropriate quantities by a recording machine and analyzed using the SPSS and MedCalc software.

Results

From 57 nodules studied, 50 nodules were evaluated with benign diagnosis and 7 nodules with the malignant diagnosis. Among all the parameters recorded by the machine, SWE. ratio provided the highest surface area under the curve and the highest sensitivity and specificity with 0.94, 100% and 84%, respectively, and a cut-off point of 1.7.

Conclusion

The 2D-SWE method and the conventional ultrasound can be good references for decision making about with the thyroid nodules.

Comparative Diagnostic Accuracy of Contrast-Enhanced Ultrasound and Shear Wave Elastography in Differentiating Benign and Malignant Lesions: A Network Meta-Analysis

Background: We performed a network meta-analysis to compare the diagnostic accuracy of contrast-enhanced ultrasound (CEUS) and shear wave elastography (SWE) in differentiating benign and malignant lesions in different body sites.

Methods: A computerized literature search of Medline, Embase, SCOPUS, and Web of Science was performed using relevant keywords. Following data extraction, we calculated sensitivity, specificity, positive likelihood ratio (LR), negative LR, and diagnostic odds ratio (DOR) for CEUS, and SWE compared to histopathology as a reference standard. Statistical analyses were conducted by MetaDiSc (version 1.4) and R software (version 3.4.3).

Results: One hundred and fourteen studies (15,926 patients) were pooled in the final analyses. Network meta-analysis showed that CEUS had significantly higher DOR than SWE (DOR = 27.14, 95%CI [2.30, 51.97]) in breast cancer detection. However, there were no significant differences between CEUS and SWE in hepatic (DOR = −6.67, 95%CI [−15.08, 1.74]) and thyroid cancer detection (DOR = 3.79, 95%CI [−3.10, 10.68]). Interestingly, ranking analysis showed that CEUS achieved higher DOR in detecting breast and thyroid cancer, while SWE achieved higher DOR in detecting hepatic cancer. The overall DOR for CEUS in detecting renal cancer was 53.44, 95%CI [29.89, 95.56] with an AUROC of 0.95, while the overall DOR for SWE in detecting prostate cancer was 25.35, 95%CI [7.15, 89.89] with an AUROC of 0.89.

Conclusion: Both diagnostic tests showed relatively high sensitivity and specificity in detecting malignant tumors in different organs. Network meta-analysis showed that CEUS had higher diagnostic accuracy than SWE in detecting breast and thyroid cancer, while SWE had higher accuracy in detecting hepatic cancer. However, the results were not statistically significant in hepatic and thyroid malignancies. Further head-to-head comparisons are needed to confirm the optimal imaging technique to differentiate each cancer type.

Diagnostic value of multimodal ultrasound imaging in differentiating benign and malignant TI-RADS category 4 nodules

Background

Differential diagnosis of benign and malignant thyroid imaging reporting and data system category 4 (TI-RADS-4) nodules can be difficult using conventional ultrasound (US). This study aimed to evaluate whether multimodal ultrasound imaging can improve differentiation and characterization of benign and malignant TI-RADS-4 nodules.

Methods

Multimodal ultrasound imaging, including US, superb microvascular imaging (SMI), and real-time elastography (RTE), were performed on 196 TI-RADS-4 nodules (78, benign; 118, malignant) in 170 consecutive patients. The sensitivity, specificity, accuracy, false negative rate (FNR), and false positive rate (FPR) of each single method and that of multimodal US imaging were determined by comparison with surgical pathology results.

Results

The sensitivity, specificity, accuracy, FNR, and FPR for US were 65.25%, 69.23%, 66.84%, 34.75%, 30.77%, respectively; for SMI were 77.97%, 93.59%, 84.18%, 22.03%, 6.41%, respectively; RTE, 80.51%, 84.62%, 82.14%, 19.49%, 15.38%; and for multimodal US imaging were 94.08%, 87.18%, 91.33%, 6.93%, 12.82%, respectively. The areas under the received operating characteristic curve for US, SMI, RTE, and multimodal US imaging in evaluating benign and malignant TI-RADS-4 nodules were 67.2%, 84.40%, 86.60%, and 95.50%, respectively.

Conclusions

The initial clinical results suggest that multimodal US imaging improves the diagnostic accuracy of TI-RADS-4 nodules and provides additional information for differentiating malignant and benign nodules.

Ultrasound elastography of the thyroid: principles and current status

Ultrasound (US) elastography has been introduced as a non-invasive technique for evaluating thyroid diseases. This paper presents a detailed description of the technical principles, peculiarities, and limitations of US elastography techniques, including strain elastography and shear-wave elastography. This review was conducted from a clinical perspective, and aimed to assess the usefulness of US elastography for thyroid diseases in specific clinical scenarios. Although its main focus is on thyroid nodules, the applications of US elastography for other thyroid diseases, such as diffuse thyroid diseases and thyroiditis, are also presented. Furthermore, unresolved questions and directions for future research are also discussed.

Comparison of strain elastography, point shear wave elastography using acoustic radiation force impulse imaging and 2D-shear wave elastography for the differentiation of thyroid nodules

PURPOSE

The aim of the study was to compare three different elastography methods, namely Strain Elastography (SE), Point Shear-Wave Elastography (pSWE) using Acoustic Radiation Force Impulse (ARFI)-Imaging and 2D-Shear Wave Elastography (2D-SWE), in the same study population for the differentiation of thyroid nodules.

MATERIALS AND METHODS

All patients received a conventional ultrasound scan, SE and 2D-SWE, and all patients except for two received ARFI-Imaging. Cytology/histology of thyroid nodules was used as a reference method. SE measures the relative stiffness within the region of interest (ROI) using the surrounding tissue as reference tissue. ARFI mechanically excites the tissue at the ROI using acoustic pulses to generate localized tissue displacements. 2D-SWE measures tissue elasticity using the velocity of many shear waves as they propagate through the tissue.

RESULTS

84 nodules (73 benign and 11 malignant) in 62 patients were analyzed. Sensitivity, specificity and NPV of SE were 73%, 70% and 94%, respectively. Sensitivity, specificity and NPV of ARFI and 2D-SWE were 90%, 79%, 98% and 73%, 67%, 94% respectively, using a cut-off value of 1.98m/s for ARFI and 2.65m/s (21.07kPa) for 2D-SWE. The AUROC (Area under the Receiver Operating Characteristic) of SE, ARFI and 2D-SWE for the diagnosis of malignant thyroid nodules were 52%, 86% and 71%, respectively. A significant difference in AUROC was found between SE and ARFI (p = 0.008), while no significant difference was found between ARFI and SWE (86% vs. 71%, p = 0.31), or SWE and SE (71% vs. 52%, p = 0.26).

CONCLUSION

pSWE using ARFI and 2D-SWE showed comparable results for the differentiation of thyroid nodules. ARFI was superior to elastography using SE.

Comparison of Strain Elastography, Shear Wave Elastography, and Conventional Ultrasound in Diagnosing Thyroid Nodules

Objective:

The purpose of this study is to compare the diagnostic performances of strain elastography (SE), shear wave elastography (SWE), and traditional ultrasound (US) features in diagnosing thyroid nodules.

Subjects and Methods:

This study included 185 adult patients with thyroid nodules who underwent conventional gray-scale US, SE, and SWE. SE was scored using a four-pattern elastographic scoring (ES) system. SWE values were presented as mean SWE values and standard derivation using Young's modules. The optimal cutoff values of the mean SWE values for predicting malignancy were determined using receiver operating characteristic (ROC) curve analysis. We used logistic regression models to test elastography as a novel significant predictor for the diagnosis of malignant nodules. The diagnostic performance of elastography parameters was compared with a traditional trained model.

Results:

Malignant thyroid nodules were stiffer for SE (ES patterns 1 and 2/3 and 4) and mean SWE values (4/17; 51.0 ± 24.4 kPa) than for benign nodules (114/50; 33.1 ± 25.2 kPa) (P < 0.01). In ROC curve analyses, a mean SWE value of 32 kPa was the optimal cutoff point, with diagnostic performance measures of 81% sensitivity, 65% specificity, a 23% positive predictive value (PPV), and 96% negative predictive value (NPV). In multivariate logistic regression, the mean SWE value (≥32 kPa) was an independent predictor for malignancy (odds ratio: 16.8; 95% confidence interval [CI]: 3.6–78.3). However, after the addition of SE and SWE to traditional US features, the C-statistic was not significantly increased compared to the traditional model (0.88, 95% CI: 0.81–0.94 vs. 0.91, 0.85–0.97, P = 0.4).

Conclusion:

In this study, we confirmed SWE as an independent predictor for malignant thyroid nodules. However, in comparing the new extended elastography model to our previous prediction model, the new extended model showed no significant difference in the diagnostic performance.

Shear wave elastography combined with the thyroid imaging reporting and data system for malignancy risk stratification in thyroid nodules

To retrospectively evaluate the diagnostic performance of shear wave elastography (SWE) and thyroid imaging reporting and data system (TI-RADS) in differentiating malignant and benign thyroid nodules. A total of 313 thyroid nodules in 227 patients were included. All thyroid nodules were underwent SWE and TI-RADS before fine needle aspiration biopsy and/or surgery. SWE elasticity indices of the maximum (Emax), mean (Emean), minimum (Emin) and elastic ratio (ER) in thyroid nodules were measured. Nodules with solid component, marked hypoechogenicity, poorly defined margins, micro-calcifications, and a taller-than-wide shape were classified as suspicious at gray-scale ultrasonography. The level of TI-RADS was determined according to the number of suspicious ultrasonography features. The combined methods of SWE and TI-RADS in thyroid nodules were calculated. In the 313 nodules, 194 were malignant, and 119 were benign. SWE and TI-RADS were significantly higher in malignant nodules than benign nodules (P < 0.001). The most accurate SWE cut-off value, 51.95 kPa for Emax, achieved a sensitivity of 81.44% and a specificity of 83.19% for discriminating malignant nodules from benign nodules. There are two methods in combination with SWE and TI-RADS. The one is "tandem" method, which has a higher specificity (95.80%), positive likelihood ratio (18.16) and positive predictive value (96.73%). The other one is "parallel" method, which shows sensitivity (94.85%), negative likelihood ratio (0.07) and negative predictive value (90.00%).We believe that the methods could be used as a simple tool to stratify the risk of thyroid nodules accurately.

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.

The Preciseness in Diagnosing Thyroid Malignant Nodules Using Shear-Wave Elastography

Our study aimed to identify more accurate results about the diagnostic role of shear-wave elastography (SWE) for thyroid malignant nodules through a meta-analysis.

Potential articles were searched in PubMed, Embase, and the Cochrane Library databases. Overall sensitivity and specificity with 95% confidence intervals (CIs) was used to represent the diagnostic accuracy of SWE. Summary receiver operating characteristic (ROC) curve was constructed to illustrate the results. In addition, χ² and I² tests were performed to assess heterogeneity. A value of p≤0.05 indicated significant heterogeneity. All the analysis was conducted in Meta-DiSc version 1.4 software.

Twenty studies were included in the analysis. There were a total of 2,907 patients and 3,397 thyroid nodules included in the meta-analysis. Overall sensitivity and specificity were 0.68 (95% CI: 0.66–0.70) and 0.85 (95% CI: 0.84–0.87), respectively. The results showed the area under curve (AUC) was 0.9041, suggesting high accuracy of SWE for differentiating benign and malignant thyroid nodules.

SWE showed high accuracy in identifying thyroid malignant nodules, suggesting it could serve as a diagnostic biomarker in thyroid nodules.

Practical Application of Elastography in the Diagnosis of Thyroid Nodules in Children and Adolescents

BACKGROUND

Ultrasound elastography is a noninvasive method of imaging based on the estimation of the mechanical properties of tissue. Data in adults indicate that decreased flexibility in comparison to the surrounding healthy tissue is characteristic of malignancy (in most thyroid carcinomas, except for follicular thyroid carcinoma). The purpose of our study was to assess the deformation of thyroid nodules and to evaluate the usefulness of elastography in predicting malignant thyroid nodules in adolescent patients.

METHODS

We examined 47 children with 62 thyroid nodules. All patients underwent elastography and fine needle aspiration cytology (FNAC).

RESULTS

Thirty-seven girls (79%) and 10 boys (21%) were included in the study. A strain ratio <2 was observed in 17 nodules (27% of the study group), a strain ratio between 2 and 4.9 in 34 nodules (55%) and a strain ratio >5 in 11 nodules (18%). According to cytological examination, 3 nodules (4.8% of the study group) were malignant. Two of them were hard (strain ratio ≥5), and 1 nodule had a strain ratio of 2.

CONCLUSIONS

Our results suggest that elastography can be complementary to conventional ultrasonography and useful while making a decision about FNAC. At the same time, it should not replace the cytological assessment of thyroid nodules in children and adolescents.

WFUMB Guidelines and Recommendations on the Clinical Use of Ultrasound Elastography: Part 4. Thyroid

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.

Elastography in Distinguishing Benign from Malignant Thyroid Nodules

AIM

The aim of this study is to test the diagnostic success of strain elastography in distinguishing benign from malignant thyroid nodules.

MATERIALS AND METHODS

The size, echogenicity, and halo integrity of 293 thyroid nodules and the presence of microcalcification in these nodules were evaluated on gray-scale examination. Doppler characteristics and elastography patterns were also evaluated and recorded. Nodules were classified in four categories (patterns 1-4) based on elastographic examination.

RESULTS

According to the cytopathological findings, 222 nodules were benign, and 71 nodules were malignant. The risk of a nodule to be malignant was 3.8 times increased by hypoechogenicity, 7.7 times increased by the presence of microcalcification, and 11.5 times increased by the absence of halo. On Doppler patterns, the presence of central vascularity increased the malignancy risk of a nodule by 5.8 times. According to the receiver operating characteristic analysis, patterns 3 and 4 were malignant, and patterns 1 and 2 were benign. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of elastography were 100%, 80.2%, 61.7%, 100%, and 85%, respectively.

CONCLUSION

Strain elastography can be used as a noninvasive method in distinguishing benign from malignant thyroid nodules and in identifying the patients who would undergo surgery.

Diagnostic Performance of Shear Wave Elastography Parameters Alone and in Combination with Conventional B-Mode Ultrasound Parameters for the Characterization of Thyroid Nodules: A Prospective, Dual-Center Study

The aims of our study were to determine whether shear wave elastography (SWE) can improve the conventional B-mode differentiation of thyroid lesions, determine the most accurate SWE parameter for differentiation and assess the influence of microcalcifications and chronic autoimmune thyroiditis on SWE values. We examined 119 patients with 169 thyroid nodules who prospectively underwent B-mode ultrasound and SWE using the same ultrasound machine. The parameters assessed using SWE were: mean elasticity within the entire lesion (SWE-whole) and mean (SWE-mean) and maximum (SWE-max) elasticity for a 2-mm-diameter region of interest in the stiffest portion of the lesion, excluding microcalcifications. The discriminant powers of a generalized estimating equation model including B-mode parameters only and a generalized estimation equation model including both B-mode and SWE parameters were assessed and compared using the area under the receiver operating characteristic curve, in association with pathologic verification. In total, 50 and 119 malignant and benign lesions were detected. In generalized estimated equation regression, the B-mode parameters associated with higher odds ratios (ORs) for malignant lesions were microcalcifications (OR = 4.3), hypo-echogenicity (OR = 3.13) and irregular margins (OR = 10.82). SWE-max was the only SWE independent parameter in differentiating between malignant and benign tumors (OR = 2.95). The area under the curve for the B-mode model was 0.85, whereas that for the model combining B-mode and SWE parameters was 0.87. There was no significant difference in mean SWE values between patients with and without chronic autoimmune thyroiditis. The results of the present study suggest that SWE is a valuable tool for the characterization of thyroid nodules, with SWE-max being a significant parameter in differentiating benign and malignant lesions, independent of conventional B-mode parameters. The combination of SWE parameters and conventional B-mode parameters does not significantly improve the diagnosis of malignant thyroid nodules. The presence of microcalcifications can influence the SWE-whole value, whereas the presence of chronic autoimmune thyroiditis may not.

Does Shear Wave Elastography Provide Additional Value in the Evaluation of Thyroid Nodules That Are Suspicious for Malignancy?

OBJECTIVES

We aimed to determine whether the integration of shear wave elastography (SWE) with conventional ultrasonography (US) improves diagnostic performance for suspicious thyroid lesions.

METHODS

For 215 thyroid lesions in 185 patients classified as Thyroid Imaging Reporting and Data System category 4 or 5 according to the findings of conventional US, SWE elasticity indices were automatically calculated. A receiver operating characteristic curve analysis was used to determine the threshold. Thyroid Imaging Reporting and Data System categories were upgraded for high-stiffness nodules and unchanged for low- and normal-stiffness nodules. The diagnostic performances were assessed and compared with histologic findings. Intraobserver and interobserver variability of SWE was assessed.

RESULTS

Elasticity indices were significantly higher in malignant versus benign nodules (P≤ .001). The minimum elasticity index (cutoff, 40.7 kPa) of the stiffest part combined with conventional US showed the highest area under the curve (0.774; 95% confidence interval, 0.682-0.866) but was not superior to conventional US (0.791; 95% confidence interval, 0.706-0.876; P = .48). Combined with the standard deviation of the elasticity index for the whole lesion (cutoff, 6.8 kPa), US yielded the highest sensitivity (95.5%; P < .001) and lowest specificity (42.1%; P < .001). Sensitivity increased and specificity decreased by adding any other SWE elasticity index. The intraobserver and interobserver reliability of SWE was fair to excellent according to the interclass correlation coefficients, with correlation coefficients of 0.765 to 0.846 (all P < .001).

CONCLUSIONS

The SWE elasticity indices of malignant thyroid nodules were significantly high. Adding SWE to conventional US did not improve diagnostic performance.

Shear wave elastography diagnosis of the diffuse sclerosing variant of papillary thyroid carcinoma: A case report

The present study aimed to report the shear wave elastography (SWE) findings in a patient with the diffuse sclerosing variant of papillary thyroid carcinoma (DSVPTC). Since patients with DSVPTC may present with typical clinicopathological features and initially appear to have Hashimoto's thyroiditis, a thorough clinical evaluation and an early diagnosis are important. A 20-year-old female patient presented with a 1-month history of a neck mass and sore throat. Conventional ultrasound and SWE were performed using an AIXPLORER system with 14-5 MHz linear transducer. The patient had undergone total thyroidectomy and bilateral neck lymph node dissection, and an intraoperative pathology consultation to confirm the malignancy of lymph node metastasis. Pathological diagnosis was DSVPTC in both lobes, with lymph node metastases in the bilateral neck. The clinical presentation and serological findings were all indicative of Hashimoto's thyroiditis. Thyroid ultrasonography revealed diffuse enlargement of the both lobes, heterogenous echogenicity without mass formation, diffuse scattered microcalcifications and poor vascularization. SWE revealed stiff values of the thyroid: The mean stiffness was 99.7 kpa, the minimum stiffness was 59.1 kpa and the maximum stiffness was 180.1 kpa. The maximum stiffness of the DSVPTC (180.1 kpa) was higher compared with the diagnostic criteria of malignant thyroid nodules (65 kPa). SWE may be considered as a novel and valuable method to diagnose DSVPC.

Diagnostic value of two-dimensional shear wave elastography in papillary thyroid microcarcinoma

Objective

The purpose of this study was to evaluate the predictability of two-dimensional shear wave elastography (2D-SWE) for papillary thyroid microcarcinoma (PTMC).

Materials and methods

One hundred and eighteen patients with 137 thyroid nodules (46 benign nodules, 91 malignant nodules) were included in this study who received conventional ultrasound (US) and 2D-SWE before fine-needle aspiration or surgery. The diagnostic performance was compared between US findings only and the combined use of US findings with 2D-SWE, which were correlated with pathology results.

Results

Receiver-operating characteristic curve analysis was performed to assess the diagnostic performance of 2D-SWE. Conventional US findings and 2D-SWE values were analyzed and compared between benign and malignant thyroid nodules. The mean values of SWE_mean, SWE_min, and SWE_max were 46.6±16.7, 26.2±9.5, and 73.6±18.1 kPa, respectively, in PTMC, which were significantly higher than those in benign tumors (27.8±12.4, 15.8±8.6, and 50.3±22.6 kPa, P<0.001). The optimal cut-off values of SWE_mean, SWE_min, and SWE_max for predicting malignancy were 34.5, 21.8, and 53.2 kPa, respectively. Taller than wide, micro-calcification, and SWE_mean were found to be independent risk factors for predicting PTMC. The overall sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of combined conventional US features with 2D-SWE parameters were 95.7%, 94.5%, 94.9%, 89.8%, and 97.7%, respectively; these were superior to those of conventional US (89.1%, 90.1%, 89.9%, 82.0%, and 93.2%).

Conclusion

The study indicates that the quantitative parameters of 2D-SWE are an independent predictive factor for diagnosing PTMC, which could provide valuable information when conventional US cannot give determinate results.

Clinical application of sonoelastography in thyroid, prostate, kidney, pancreas, and deep venous thrombosis

This article reviews the clinical applications of current ultrasound elastography methods in non-hepatic conditions including thyroid nodules, prostate cancer, chronic kidney disease, solid renal lesions, pancreatic lesions, and deep vein thrombosis. Pathophysiology alters tissue mechanical properties via ultrastructural changes including fibrosis, increased cellularity, bleeding, and necrosis, creating a target biomarker, which can be imaged qualitatively or quantitatively with US elastography. US elastography methods can add information to conventional US methods and improve the diagnostic performance of conventional US in a range of disease processes.

Comparison of Diagnostic Accuracy of Real-Time Elastography and Shear Wave Elastography in Differentiation Malignant From Benign Thyroid Nodules

Thyroid nodules are relatively more prevalent in iodine-deficiency area, and the incidence increased sharply in the past decade in these areas. Workup of malignant from benign nodules in clinic was the main problem for managing thyroid nodules.An overall search for the articles about the diagnostic performance of real-time elastography (RTE) and shear wave elastography (SWE) before April 2015 in the databases of PubMed, Embase, and Google scholar. The pooled sensitivity, specificity, and summary receiver operating characteristic (SROC) curve were obtained from individual studies with a random-effects model. Subgroup and meta-regression analysis were also performed.Fifty-six studies involved in 2621 malignant nodules and 7380 benign nodules were contained in our meta-analysis. The pooled sensitivity and specificity of RTE was 83.0% and 81.2%, which is higher than SWE (sensitivity: 78.7%, specificity: 80.5%). The areas under the SROC curve of RTE and SWE were 0.885 and 0.842 respectively. RTE had higher diagnostic value for Caucasians than Asians. Stran ratio (SR) assessment had higher diagnostic performance than elasticity score (ES) system. Similarly, it had higher diagnostic value when malignant nodules were more than 50.In summary, the results revealed that RTE had higher diagnostic performance than SWE in differentiating malignant from benign nodules. However, future international multicenter studies in the region of thyroid risk need to further assess the diagnostic performance of RTE.

Shear Wave Elastography in the Diagnosis of Thyroid Nodules with Coexistent Chronic Autoimmune Hashimoto’s Thyroiditis

Objective

To evaluate the diagnostic performance of shear wave elastography (SWE) in the differentiation of malignant and benign thyroid nodules with coexistent Hashimoto’s thyroiditis (HT).

Study Design

Case series with chart review.

Setting

Tertiary general hospital.

Subjects and Methods

From September 2012 to January 2014, conventional ultrasound and SWE were performed on 243 patients with 286 thyroid nodules with histologic results. The HT group consisted of 93 patients with 117 nodules. The non-HT group consisted of 140 patients with 169 nodules.

Results

In the benign and malignant nodules, there were no significant differences of the mean, minimum, or maximum SWE values between HT and non-HT groups ( P = .158-.945). However, SWE values of extranodular tissue were significantly higher in the HT group ( P = .000-.011). In the HT group, the maximum SWE value showed the highest area under the receiver operating characteristic curve (0.817; 95% confidence interval, .735-.900), and there were no significant differences when compared with other SWE parameters ( P = .669-.848). In the multivariate analysis, hypoechogenicity (odds ratio = 9.855, P = .002), microcalcification (odds ratio = 3.977, P = .046), and maximum SWE value (odds ratio = 40.712, P < .001) were independent predictors of thyroid malignancy.

Conclusions

SWE could be performed to obtain a differential diagnosis between malignant and benign thyroid nodules, including nodules with coexistent HT. Although all the SWE parameters within a 2-mm region of interest that was placed on the stiffest region could be applied, we suggest that the maximum value of nodules harbored within a Hashimoto’s gland be used.

Qualitative elastography can replace thyroid nodule fine-needle aspiration in patients with soft thyroid nodules. A systematic review and meta-analysis

CONTEXT

Only a minority of thyroid nodules is malignant; nevertheless, many invasive diagnostic procedures are performed to distinguish between benign and malignant nodules. Qualitative ultrasound elastography is a non-invasive technique to evaluate thyroid nodules.

OBJECTIVE

To investigate the diagnostic value of qualitative elastography in distinguishing benign from malignant thyroid nodules in patients referred for fine-needle aspiration (FNA).

DATA SOURCES

A systematic literature search (PubMed, Embase and Cochrane Library) was performed.

STUDY SELECTION

Included studies reported thyroid nodule elastography color scores and the related cytologic or histologic findings in patients with a thyroid nodule referred for FNA.

DATA EXTRACTION

Two independent reviewers extracted study data and assessed study quality. Pooled sensitivities and specificities of different populations were calculated using a bivariate Bayesian framework.

DATA SYNTHESIS

Twenty studies including thyroid nodules were analyzed. Pooled results of elastography indicate a summary sensitivity of 85% (95% confidence interval [CI], 79-90%) and specificity of 80% (95% CI, 73-86%). The respective pooled negative predictive and positive predictive values were 97% (95% CI, 94-98%) and 40% (95% CI, 34-48%). The pretest probability of a benign nodule was 82%. Only 3.7% of the false-negative nodules was a follicular thyroid carcinoma. A pooled negative predictive value of 99% (95% CI, 97-100%) was found when only complete soft nodules (Asteria elastography 1) were classified as benign, which included 14% of the studied population.

CONCLUSIONS

Elastography has a fair specificity and sensitivity for diagnostic accuracy. Its major strength entails the detection of benignity, especially when only completely soft nodules are qualified as benign. The outcomes of our analysis show that FNA could safely be omitted in patients referred for analysis of their thyroid nodule when elastography shows it to be completely soft (Asteria elastography 1). This could prevent unnecessary invasive diagnostic procedures in a substantial portion of patients.

Two-dimensional shear wave elastography as promising diagnostic tool for predicting malignant thyroid nodules: a prospective single-centre experience

OBJECTIVES

To evaluate the diagnostic performance of two-dimensional shear wave elastography (2D-SWE) in distinguishing malignant from benign thyroid nodules.

METHODS

A total of 331 focal thyroid nodules from 271 patients scheduled for fine-needle aspiration or thyroid surgery were included. After a routine conventional ultrasound evaluation, 2D-SWE examinations were performed to obtain 2D-SWE measurements on a colour-coded mapping, which were then correlated with pathology results.

RESULTS

A total of 230 nodules were benign and 101 were malignant on pathology. The areas under the receiver operating characteristic curve (AUC) of mean and minimum values in the largest region of interest (ROI) over the whole nodule, and mean, maximum and minimum values in 2-mm ROI over the stiffest area of the nodule were 0.794, 0.673, 0.808, 0.805 and 0.799, respectively. The most accurate cut-off value, 39.3 kPa, for mean value in a 2-mm ROI achieved 66.3 % sensitivity and 84.4 % specificity to discriminate malignancy. Nodule size correlated with 2D-SWE value for malignant nodules (P < 0.01). In the group of nodules ≤10 mm, the AUC was 0.730, while it was 0.883 in nodules sized 11-30 mm and 0.821 in nodules >30 mm.

CONCLUSION

2D-SWE is a promising diagnostic tool for discriminating malignant thyroid nodules, although the performance for nodules ≤10 mm is not satisfactory.