Prospective Evaluation of Semiquantitative Strain Ratio and Quantitative 2D Ultrasound Shear Wave Elastography (SWE) in Association with TIRADS Classification for Thyroid Nodule Characterization

Abstract

Purpose To evaluate the diagnostic performance of strain ratio elastography (SRE) and shear wave elastography (SWE) alone and in combination with Thyroid Imaging Reporting and Data System (TIRADS) classification parameters to improve differentiation between benign and malignant thyroid nodules. Materials and Methods In this prospective study benign (n = 191) and malignant (n = 52) thyroid nodules were examined with high-resolution ultrasound (US) features using the TIRADS lexicon and SRE semiquantitative and SWE quantitative findings using histology or cytology as the gold standard with a 12-month follow-up. Sensitivity (Se), specificity (Sp) and the area under the ROC curve (AUROC) were used to evaluate the diagnostic performance of each feature and combinations of the methods. Results TIRADS score showed a sensitivity of 59.6 %, a specificity of 83.8 % with an AUROC of 0.717, a PPV of 50.0 % and an NPV of 88.4 %. SRE yielded the highest performance with a sensitivity of 82.7 %, a specificity of 92.7 % with AUROC of 0.877, a PPV 75.4 % and an NPV of 95.2 %. SWE (kPa) had a sensitivity and specificity of 67.3 % and 82.7 %, respectively, with an AUROC of 0.750, a PPV of 51.5 % and an NPV of 90.3 %. Differences were significant for SRE only but not for SWE. Conclusion Ultrasound elastography may improve thyroid nodule discrimination. In particular, SRE has a better performance than TIRADS classification, while their combination improves sensitivity.

Elastography for the diagnosis of high-suspicion thyroid nodules based on the 2015 American Thyroid Association guidelines: a multicenter study

“…Another controversial topic is whether the combined application of US and ES may provide better results for thyroid nodule characterization. The results of the present research demonstrated that the sensitivity and NPV were dramatically higher with the combination than with the TI-RADS and ES alone, and the accuracy was higher with the combination than with the TI-RADS alone but not with the ES alone, consistent with the study by Cantisani [35]. However, the specificity decreased after the two were combined.…”

“…Although shear wave elastography (SWE) has drawn more attention in recent years and has been reported to be more accurate than USE in some studies [30][31][32], Tian et al's and Hu et al's meta-analysis showed that USE had a better diagnostic performance than SWE, with comparable specificity between methods [33,34]. Even more recently, a prospective study comprising 243 nodules revealed that USE yielded the highest performance compared with the TI-RADS score and SWE [35]. The aforementioned data confirm that USE is still a promising diagnostic tool for discriminating malignant from benign thyroid nodules.…”

Contemporary Thyroid Nodule Evaluation and Management

“…To address this problem, the International Thyroid Nodule Ultrasound Working Group, a multidisciplinary alliance of physicians with expertise in thyroid nodule sonography, is attempting to devise a unified, international set of guidelines that is based on a validated lexicon and incorporates state-of-the-art techniques and research data ( 39 ). Standard B-mode US examinations can also be expanded to include elastographic (strain or shear-wave techniques) analysis ( 40 ) of the stiffness of the nodular tissue and contrast-enhanced assessments of its perfusion and vascularity ( 41 ). Both approaches have produced promising results and their use for US-based risk-stratification has been proposed ( 40 , 41 ).…”

TI-RADS Diagnostic Performance: Which Algorithm Is Superior and How Elastography and 4D Vascularity Improve the Malignancy Risk Assessment

“…Ideally, a uniform, standardized US classification should be used internationally by all clinicians. Given their important prevalence, many guidelines and papers focused their work on developing the best risk assessment and therapeutic strategies, but their recommendations slightly differ in some respects [3,4].…”