Utility of shear wave elastography to detect papillary thyroid carcinoma in thyroid nodules: efficacy of the standard deviation elasticity

Impact of Region-of-Interest Size on the Diagnostic Performance of Shear Wave Elastography in Differentiating Thyroid Nodules

This study investigated the impact of different region-of-interest (ROI) sizes (Max, 1 mm, and 2 mm) on shear wave elastography (SWE) in differentiating between malignant and benign thyroid nodules. The study cohort comprised 129 thyroid nodules (50 malignant, 79 benign) and 78 normal subjects. Diagnostic efficacy was assessed through pairwise comparisons of area under the curve (AUC) values in receiver operating characteristic analysis by using DeLong's test. Our results indicated significant differences in all SWE elasticity metrics between the groups, with malignant nodules exhibiting higher values than benign nodules (p < 0.05). Smaller ROIs (1 and 2 mm) were found to outperform the max ROI in terms of diagnostic accuracy, particularly for the Emax and Emin elasticity metrics. Emax(1mm) had the highest diagnostic accuracy, with an AUC of 0.883, sensitivity of 74.0%, and specificity of 86.1%. This study underscores the significant influence of ROI size selection on the diagnostic performance of SWE, offering valuable insights for future research and clinical applications in thyroid nodule assessment.

Contrast-enhanced ultrasound and shear wave elastography in the diagnosis of ACR TI-RADS 4 and 5 category thyroid nodules coexisting with Hashimoto's thyroiditis

Objective

This study aims to evaluate the value of contrast-enhanced ultrasound (CEUS), shear wave elastography (SWE), and their combined use in the differentiation of American College of Radiology (ACR) thyroid imaging reporting and data system (TI-RADS) 4 and 5 category thyroid nodules coexisting with Hashimoto's thyroiditis (HT).

Materials and methods

A total of 133 pathologically confirmed ACR TI-RADS 4 and 5 category nodules coexisting with HT in 113 patients were included; CEUS and SWE were performed for all nodules. The sensitivity, specificity, negative predictive value (NPV), positive predictive value (PPV), accuracy, and the area under the receiver operating characteristic curve (AUC) of the SWE, CEUS, and the combined use of both for the differentiation of benign and malignant nodules were compared, respectively.

Results

Using CEUS alone, the sensitivity, specificity, PPV, NPV, and accuracy were 89.2%, 66.0%, 81.3%, 78.6%, and 80.5%, respectively. Using SWE alone, Emax was superior to Emin, Emean, and Eratio for the differentiation of benign and malignant nodules with the best cutoff Emax >46.8 kPa, which had sensitivity of 65.1%, specificity of 90.0%, PPV of 91.5%, NPV of 60.8%, and accuracy of 74.4%, respectively. Compared with the diagnostic performance of qualitative CEUS or/and quantitative SWE, the combination of CEUS and SWE had the best sensitivity, accuracy, and AUC; the sensitivity, specificity, PPV, NPV, accuracy, and AUC were 94.0%, 66.0%, 82.1%, 86.8%, 83.5%, and 0.80 (95% confidence interval: 0.713, 0.886), respectively.

Conclusion

In conclusion, CEUS and SWE were useful for the differentiation of benign and malignant ACR TI-RADS 4 and 5 category thyroid nodules coexisting with HT. The combination of CEUS and SWE could improve the sensitivity and accuracy compared with using CEUS or SWE alone. It could be a non-invasive, reliable, and useful method to differentiate benign from malignant ACR TI-RADS 4 and 5 category thyroid nodules coexisting with HT.

Shear wave elastography as a quantitative biomarker of diabetic peripheral neuropathy: A systematic review and meta-analysis

Background

Diabetic peripheral neuropathy (DPN) is one of the most common chronic complications of diabetes and the strongest initiating risk factor for diabetic foot ulceration. Early diagnosis of DPN through screening measures is, therefore, of great importance for diabetic patients. Recently, shear wave elastography (SWE) has been used as a method that is complementary to neuroelectrophysiological examination in the diagnosis of DPN. We aimed to conduct a meta-analysis based on currently available data to evaluate the performance of tibial nerve stiffness on SWE for diagnosing DPN.

Methods

Both PubMed, EMBASE, the Cochrane Library, and Web of Science were searched for studies that investigated the diagnostic performance of SWE for DPN up to March 1th, 2022. Three measures of diagnostic test performance, including the summary area under receiver operating characteristics curve (AUROC), the summary sensitivity and specificity, and the summary diagnostic odds ratios were used to assess the diagnostic accuracy of SWE. All included studies were published between 2017 and 2021.

Results

Six eligible studies (with 170 DPN patients, 28 clinically defined DPN patients, 168 non-DPN patients, and 154 control participants) that evaluated tibial nerve stiffness were included for meta-analysis. The summary sensitivity and specificity of SWE for tibial nerve stiffness were 75% (95% confidence interval [CI]: 68–80%) and 86% (95% CI: 80–90%), respectively, and the summary AUROC was 0.84 (95% CI: 0.81–0.87), for diagnosing DPN. A subgroup analysis of five two-dimensional SWE studies revealed similar diagnostic performance, showing the summary sensitivity and specificity of 77% (95% CI: 69–83%) and 86% (95% CI: 79–91%), respectively, and a summary AUROC value of 0.86 (95% CI: 0.83–0.89).

Conclusions

SWE is found to have good diagnostic accuracy for detecting DPN and has considerable potential as an important and noninvasive adjunctive tool in the management of patients with DPN.

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.

Evaluation of ultrasound point shear wave elastography reliability in an elasticity phantom

PURPOSE

To date, limited studies have specifically addressed the reliability of ultrasound point shear-wave elastography (pSWE). Therefore, the aim of the present study was to assess the reproducibility of ultrasound pSWE within and between operators using two ultrasound scanners.

METHODS

iU22 and EPIQ7 ultrasound scanners were used to assess the reliability of pSWE measurements of four inclusions [L I (8 kPa), L II (14 kPa), L III (48 kPa), and L IV (80 kPa)] at a depth of 3.5 cm in an elasticity phantom using a curvilinear 5-1 MHz transducer. The intraoperator, inter-operator, and inter-scanner reproducibility of pSWE was assessed using intraclass correlation coefficients (ICCs). Bland-Altman plots were used to establish bias and limits of agreement (LoA) between measurements. The accuracy of pSWE from manufacturer values was determined using the one-sample t-test.

RESULTS

Intra-operator agreement was excellent, with an ICC >0.90. The bias in measurements for operator A was -0.36±3.13 kPa (LoA, -6.47 to 5.75), and for operator B it was 1.97±6.29 kPa (LoA, -10.25 to 14.21). Inter-operator agreement was excellent, with an ICC of 0.95. The bias in measurements between operators was -0.42±5.00 kPa (LoA, -10.24 to 9.38). The inter-scanner agreement between EPIQ7 and iU22 was excellent, with an ICC of 0.96. The bias in measurements between scanners was 1.74±4.44 kPa (LoA, -6.95 to 10.45). There was significant overestimation for L I (17.75%) and L II (31.14%) and underestimation for L III (-15.28%) and L VI (-98.00%) relative to the manufacturer-reported values.

CONCLUSION

Phantom ultrasound pSWE was reproducible within and between operators, and between Philips ultrasound scanners; further studies using different ultrasound systems and transducers are required.

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.

Evaluation of Ultrasound Elastography Combined With Chi-Square Automatic Interactive Detector in Reducing Unnecessary Fine-Needle Aspiration on TIRADS 4 Thyroid Nodules

Background

Conventional ultrasound diagnosis of thyroid nodules (TNs) had a high false-positive rate, resulting in many unnecessary fine-needle aspirations (FNAs).

Objective

This study aimed to establish a simple algorithm to reduce unnecessary FNA on TIRADS 4 TNs using different quantitative parameters of ultrasonic elasticity and chi-square automatic interactive detector (CHAID) method.

Methods

From January 2020 to May 2021, 432 TNs were included in the study, which were confirmed by FNA or surgical pathology. Each TN was examined using conventional ultrasound, sound touch elastography, and Shell measurement function. The quantitative parameters E and E_shell were recorded, and the E_shell/E values were calculated for each TN. The diagnostic performance of the quantitative parameters was evaluated using the receiver operating characteristic curves. The CHAID was used to classify and analyze the quantitative parameters, and the prediction model was established.

Results

A total of 226 TNs were malignant and 206 were benign. E_shell and E_shell/E ratio were included in the classification algorithm, which showed a depth of two ramifications (E_shell/E ≤ 0.988 or 0.988–1.043 or >1.043; if E_shell/E ≤ 0.988, then E_shell ≤ 64.0 or 64.0–74.0 or >74.0; if E_shell/E = 0.988–1.043, then E_shell ≤ 66.0 or > 66.0; if E_shell/E >1.043, then E_shell ≤ 69.0 or >69.0). The unnecessary FNAs could have been avoided in 57.3% of the cases using this algorithm.

Conclusion

The prediction model using quantitative parameters had high diagnostic performance; it could quickly distinguish benign lesions and avoid subjective influence to some extent.

Diagnostic performance of C-TIRADS combined with SWE for the diagnosis of thyroid nodules

OBJECTIVE

To explore the value of the optimal parameters of shear wave elastography (SWE) to enhance the identification of benign and malignant thyroid nodules by C-TIRADS.

METHODS

The two-dimensional ultrasonography images and SWE images of 515 patients with a total of 586 thyroid nodules were retrospectively analyzed. The nodules were divided into the D ≤10 mm and D >10 mm groups according to size and were graded by C-TIRADS. With the pathological results as the gold standard, the receiver operating characteristic (ROC) curves were drawn, and the area under the curve (AUC) was calculated to compare the diagnostic performances of C-TIRADS, SWE, and the combination of the two on the benign and malignant thyroid nodules.

RESULTS

The ROC showed that the AUC of the maximum elastic modulus (0.875) was higher than that of the mean elastic modulus (0.798) and elasticity ratio (0.772), with an optimal cutoff point of 51 kPa, which was the optimal parameter to distinguish the malignant from the benign nodules (P < 0.001). In the D ≤10 mm group, the AUC of TIRADS combined with SWE (0.955) was elevated by 0.172 compared with the application of C-TIRADS alone (0.783), and the difference was statistically significant (P < 0.05). In the D >10 mm group, the AUC of TIRADS combined with SWE (0.904) was elevated by 0.076 compared with the application of C-TIRADS alone (0.828), and the difference was statistically significant (P < 0.05). Among all nodules, the application of C-TIRADS alone had a sensitivity of 88.14%, a specificity of 74.56%, and an accuracy of 85.50% in diagnosing benign and malignant thyroid nodules, while the sensitivity, specificity, and accuracy were 93.22%, 90.35%, and 92.66%, respectively, in combination with SWE.

CONCLUSION

The diagnostic performance of SWE in combination with TIRADS was better than that of SWE or C-TIRADS alone. Here, SWE enhanced the diagnostic performance of C-TIRADS for the benign and malignant thyroid nodules, most significantly for nodules with D ≤10 mm.

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.

Evaluation of thyroid nodules by shear wave elastography: a review of current knowledge

PURPOSE

Shear wave elastography (SWE), as a tool for diagnosing thyroid malignancy, has gathered considerable attention during the past decade. Diverging results exist regarding the diagnostic performance of thyroid SWE.

METHODS

A comprehensive literature review of thyroid SWE was conducted using the terms "Thyroid" and "shear wave elastography" in PubMed.

RESULTS

The majority of studies found SWE promising for differentiating malignant and benign thyroid nodules on a group level, whereas results are less convincing on the individual level due to huge overlap in elasticity indices. Further, there is lack of consensus on the optimum outcome reflecting nodule elasticity and the cut-off point predicting thyroid malignancy. While heterogeneity between studies hinders a clinically meaningful meta-analysis, the results are discussed in a clinical perspective with regard to applicability in clinical practice as well as methodological advantages and pitfalls of this technology.

CONCLUSION

Technological as well as biological hindrances seem to exist for SWE to be clinically reliable in assessing benign and malignant thyroid nodules. Structural heterogeneity of thyroid nodules in combination with operator-dependent factors such as pre-compression and selection of scanning plane are likely explanations for these findings. Standardization and consensus on the SWE acquisition process applied in future studies are needed for SWE to be considered a clinically reliable diagnostic tool for detection of thyroid cancer.

Assessment of perinodular stiffness in differentiating malignant from benign thyroid nodules

OBJECTIVE

We evaluated the diagnostic accuracy of perinodular stiffness, four risk stratification systems (RSSs) (KWAK-TIRADS, ACR-TIRADS, EU-TIRADS, and C-TIRADS), and the combination of perinodular stiffness and the four RSSs in differentiating malignant from benign thyroid nodules (TNs).

METHODS

A total of 788 TNs in 726 patients were examined with conventional ultrasound (US) examination and sound touch elastography (STE). All TNs were classified by each of the four RSSs. The stiffness inside (E) the TNs was measured by STE. The stiffness of the 2.0-mm perinodular region (Eshell) was measured with the Shell measurement function of STE. The diagnostic performances of four RSSs, the E values, and the Eshell values were evaluated. All TNs were further divided into subgroups based on size (≤ 10 mm group and > 10 mm group).

RESULTS

Ninety-six TNs were classified as benign and 692 as malignant. Among the single-method approaches, ACR-TIRADS showed the highest AUC (0.77) for differentiating malignant from benign TNs for all TNs included. Eshell showed the highest AUC (0.75) in differentiating malignant from benign TNs for TNs with sizes ≤ 10 mm, and there were no significant differences in AUC among all single methods for diagnosis of TNs with sizes > 10 mm (P > 0.05). The combination of C-TIRADS and Eshell/E yielded the highest AUC for all TNs (0.83) and for TNs with size ≤ 10 mm (0.85) compared with other combinations.

CONCLUSIONS

Eshell/E combined with conventional US improves the diagnostic accuracy in TNs and may reduce unnecessary fine-needle aspiration.

Incremental diagnostic value of shear wave elastography combined with contrast-enhanced ultrasound in TI-RADS category 4a and 4b nodules

PURPOSE

To evaluate the diagnostic value of shear wave elastography (SWE) combined with contrast-enhanced ultrasonography (CEUS) in diagnosing thyroid imaging reporting and data system (TI-RADS) category 4a and 4b nodules.

METHODS

TI-RADS, SWE, and CEUS features of 71 thyroid nodules (23 benign, 48 malignant) confirmed by postoperative pathological results were retrospectively analyzed. The diagnostic efficiency of each single method and that of a combination of three methods were compared.

RESULTS

The sensitivity and specificity in diagnosing thyroid nodules were 70.83% and 65.22% for TI-RADS, 68.75% and 91.30% for SWE, 77.08% and 78.26% for CEUS, and 91.67% and 95.65% for TI-RADS + SWE + CEUS, respectively. The area under the curve for TI-RADS, SWE, CEUS, and TI-RADS + SWE + CEUS in diagnosing thyroid nodules were 0.680, 0.839, 0.799, and 0.937, respectively. A significant difference was observed between a combination of the three methods and any of them alone (p < 0.05).

CONCLUSION

Combining SWE and CEUS improves the differential diagnosis of TI-RADS category 4a and 4b nodules.

Re-Evaluation of 162 Malignant Thyroid Nodules that were Interpreted as Benign Based on Ultrasound Findings

Purpose

The goal of this study was to estimate the risk of malignant thyroid nodules being interpreted as benign based on ultrasound findings and to clarify the pathological features of these malignant nodules.

Materials and Methods

We retrospectively re-evaluated ultrasound and pathological findings for 162 malignant thyroid nodules that were initially interpreted as benign based on ultrasound findings at Kuma Hospital between April 2012 and June 2015.

Results

The incidences of malignancy among “benign” thyroid nodules were 0.5% overall and 6.2% among resected nodules. In addition, 82.7% of thyroid nodules that were originally judged to have low or very low suspicion patterns were subsequently re-categorized as having high or intermediate suspicion patterns. The incidences of irregular margins (63.6%) and low echogenicity (36.4%) were higher than those of punctate microcalcification (17.9%) and the taller-than-wide shape (20.4%). Among microcarcinomas, the incidences were 65.7% for irregular margins and 51.4% for low echogenicity. Rim calcification with small extrusive soft tissue components and extrathyroidal extensions were not observed. After re-evaluation, 40.0% of papillary thyroid carcinomas remained benign based on their variants, such as the encapsulated, follicular, macrofollicular, and oxyphilic cell variants.

Conclusion

We conclude that more careful observation, especially for lesions with irregular margins and low echogenicity, can help improve the diagnostic accuracy of thyroid ultrasonography. Furthermore, greater care may decrease the incidence of malignancy among thyroid nodules with low or very low suspicion patterns. Some variants of papillary thyroid carcinoma can have benign ultrasound findings.