Complementary Role of Elastography Using Carotid Artery Pulsation in the Ultrasonographic Assessment of Thyroid Nodules: A Prospective Study

Evaluation of US Elastography in Thyroid Nodule Diagnosis: The ElaTION Randomized Control Trial

Background There is variable evidence and no randomized trials on the benefit of US elastography-guided fine-needle aspiration cytology (FNAC) over conventional US-guided FNAC alone for thyroid nodules. Purpose To compare the efficacy of US elastography-guided FNAC versus US-guided FNAC in reducing nondiagnostic rates for thyroid nodules. Materials and Methods A pragmatic, multicenter randomized controlled trial was performed at 18 secondary and tertiary hospitals across England between February 2015 and September 2018. Eligible adults with single or multiple thyroid nodules who had not previously undergone FNAC were randomized (1:1 ratio) to US elastography FNAC (intervention) or conventional US FNAC (control). The primary outcome was the proportion of patients who have a nondiagnostic cytologic Thy1 (British Thyroid Association system) result following the first FNAC. Results A total of 982 participants (mean age, 51.3 years ± 15 [SD] [IQR, 39-63]; male-to-female ratio, 1:4) were randomized. Of the 493 participants who underwent US elastography, 467 (94.7%) were examined with strain US elastography. There was no difference between the two arms in the nondiagnostic (Thy1) rate following the first FNAC (19% vs 16%; risk difference [RD], 0.03 [95% CI: -0.01, 0.07]; P = .11) or in the median time to reach the final definitive diagnosis (3.3 months [IQR, 1.5-6.4] for US elastography FNAC vs 3.4 months [IQR, 1.5-6.2] for US FNAC). All sensitivity analyses supported the primary analysis. Fewer participants in the US elastography FNAC arm underwent diagnostic hemithyroidectomy than in the US FNAC arm (183 of 493 [37%] vs 196 of 489 [40%]), but this was not statistically significant (adjusted RD, 0.02 [95% CI: -0.06, 0.01]; P = 0.15). There was no evidence of a difference in malignancy rates between the two arms: 70 of 493 (14%) in US elastography FNAC arm versus 79 of 489 (16%) in US FNAC arm (P = .39). There was also no difference in the rate of benign histologic findings between the groups (RD, -0.01 [95% CI: -0.04, 0.03]; P = .7). Conclusion Strain US elastography does not appear to have additional benefit over conventional US FNAC in the diagnosis of malignancy in thyroid nodules. Clinical trial registration no. ISRCTN18261857 Published under a CC BY 4.0 license. Supplemental material is available for this article. See also the editorial by Isikbay and Harwin in this issue.

Comparison of artificial intelligence, elastic imaging, and the thyroid imaging reporting and data system in the differential diagnosis of suspicious nodules

Background

Ultrasound is widely used for detecting thyroid nodules in clinical practice. This retrospective study aimed to assess the diagnostic efficacy of the American College of Radiology Thyroid Imaging Reporting and Data System (ACR-TIRADS), S-Detect, and elastography of the carotid artery for suspicious thyroid nodules and to determine the complementary value of artificial intelligence and elastography.

Methods

Between January 2021 and November 2021, 101 consecutive patients with 138 thyroid nodules were enrolled in The First Hospital of China Medical University. All nodules were evaluated using ACR-TIRADS categories (TR), S-Detect, and elastography, and then the diagnostic performance of the different methods and the combined assessment were compared. The inclusion criteria were the following: (I) TR3, TR4, and TR5 nodules, which were defined as "suspicious nodules"; (II) patients who had surgical or cytopathological results after ultrasound examination; and (III) voluntary enrollment in this study. Meanwhile, the exclusion criteria were the following: (I) TR1 and TR2 nodules, (II) patients who had undergone fine-needle aspiration before ultrasound examination, and (III) inconclusive cytologic findings.

Results

A total of 71 patients (12 men and 59 women) with 94 suspicious thyroid nodules (42 benign nodules and 52 malignant nodules) were finally included in this study. S-Detect had a significantly better sensitivity than did ACR-TIRADS [S-Detect: 98.1%, 95% confidence interval (CI): 89.7-100.0%; ACR-TIRADS: 84.6%, 95% CI: 71.9-93.1%; P=0.036], but its specificity was much lower (S-Detect: 19.0%; 95% CI: 8.6-34.1%; ACR-TIRADS: 40.5%, 95% CI: 25.6-56.7%; P=0.032). The accuracy was not significantly different between S-Detect (62.8%; 95% CI: 52.2-72.5%) and ACR-TIRADS (64.9%; 95% CI: 54.4-74.5%) (P=0.761). The elasticity contrast index (ECI) was not definitively useful in identifying suspicious thyroid nodules (P=0.592). Compared with the use of ACR-TIRADS and S-Detect alone, the specificity (45.2%; 95% CI: 29.8-61.3%), positive predictive value (65.2%; 95% CI: 52.4-76.5%), accuracy (66.0%; 95% CI: 55.5-75.4%), and the area under the receiver operating characteristic curve (0.640; 95% CI: 0.534-0.736) of their combination were higher but not significantly so.

Conclusions

At present, S-Detect cannot replace manual diagnosis, and the value of elastography of the carotid artery in diagnosing suspected thyroid nodules remains unclear.

Comparison of diagnostic value of SWE, FNA and BRAF gene detection in ACR TI-RADS 4 and 5 thyroid nodules

OBJECTIVES: To compare the diagnostic value of shear wave elastography (SWE), fine needle aspiration (FNA) and BRAF gene detection (BRAFV600E gene mutation detection) in ACR TI-RADS 4 and 5 thyroid nodules. METHODS: SWE images, FNA cytological results and BRAF detection results of ACR TI-RADS 4 and 5 thyroid nodules confirmed by pathology were analyzed retrospectively. The receiver operating characteristic (ROC) curve was drawn to determine the best cutoff value of SWE Emax. In the combined diagnosis of SWE, FNA and BRAF, firstly, the nodules with BRAF gene mutation were included in the positive ones, secondly, the nodules with benign and malignant FNA were included in the FNA + SWE or FNA + SWE + BRAF negative and positive ones respectively, finally, for FNA uncertain nodules: those whose SWE Emax were less than or equal to the cutoff value were included in FNA + SWE or FNA + SWE + BRAF negative ones, and those whose SWE Emax were greater than the cutoff value were included in positive ones. The diagnostic efficacy of SWE, FNA, SWE + FNA, FNA + BRAF and their combination in ACR TI-RADS 4 and 5 thyroid nodules were compared. RESULTS: The ROC curve showed that the best cutoff value of SWE Emax was 40.9 kpa, and the area under ROC curve (AUC) was 0.842 (0.800∼0.885). The sensitivity, specificity and accuracy of SWE were 76.3% (270/354), 75.5% (80/106) and 76.1% (350/460), respectively. The sensitivity, specificity and accuracy of FNA were 58.2% (206/354), 88.7% (94/106) and 65.2(300/460), respectively. The sensitivity, specificity and accuracy of FNA + BRAF were 95.5% (338/354), 88.7% (94/106) and 93.9% (432/460), respectively. The sensitivity, specificity and accuracy of SWE + FNA were 85.9% (304/354), 98.1% (104/106) and 88.7% (408/460), respectively. The sensitivity, specificity and accuracy of SWE + FNA + BRAF were 98.3% (348/354), 98.1% (104/106) and 98.3% (452/460), respectively. For the diagnostic accuracy, SWE + FNA + BRAF >  FNA + BRAF >  FNA + SWE >  SWE >  FNA, the difference was statistically significant (all P >  0.05). CONCLUSIONS: For ACR TI-RADS 4 and 5 thyroid nodules, SWE and FNA have high diagnostic efficiency. For the diagnostic accuracy, FNA + BRAF is better than FNA + SWE. FNA combination with BRAF gene detection further improves the diagnostic sensitivity and accuracy of FNA. The combined application of the three is the best.

2021 Korean Thyroid Imaging Reporting and Data System and Imaging-Based Management of Thyroid Nodules: Korean Society of Thyroid Radiology Consensus Statement and Recommendations

Incidental thyroid nodules are commonly detected on ultrasonography (US). This has contributed to the rapidly rising incidence of low-risk papillary thyroid carcinoma over the last 20 years. The appropriate diagnosis and management of these patients is based on the risk factors related to the patients as well as the thyroid nodules. The Korean Society of Thyroid Radiology (KSThR) published consensus recommendations for US-based management of thyroid nodules in 2011 and revised them in 2016. These guidelines have been used as the standard guidelines in Korea. However, recent advances in the diagnosis and management of thyroid nodules have necessitated the revision of the original recommendations. The task force of the KSThR has revised the Korean Thyroid Imaging Reporting and Data System and recommendations for US lexicon, biopsy criteria, US criteria of extrathyroidal extension, optimal thyroid computed tomography protocol, and US follow-up of thyroid nodules before and after biopsy. The biopsy criteria were revised to reduce unnecessary biopsies for benign nodules while maintaining an appropriate sensitivity for the detection of malignant tumors in small (1-2 cm) thyroid nodules. The goal of these recommendations is to provide the optimal scientific evidence and expert opinion consensus regarding US-based diagnosis and management of thyroid nodules.

Comparison of ACR TI-RADS, Kwak TI-RADS, ATA guidelines and KTA/KSThR guidelines in combination with SWE in the diagnosis of thyroid nodules

OBJECTIVE

To compare the diagnostic efficacy of ACR TI-RADS, Kwak TI-RADS, ATA guidelines and KTA/KSThR guidelines in combination with shear wave elastography (SWE) for thyroid nodules.

METHODS

The retrospective study included 566 thyroid nodules with maximum diameter≥5 mm which confirmed by FNA cytology or/and surgical pathology. The sensitivity, specificity, accuracy, Youden index of diagnosis of thyroid nodules by ACR TI-RADS, Kwak TI-RADS, ATA guidelines, KTA/KSThR guidelines and SWE were calculated. The ROC curve was drawn to determine the cut-off values of the four ultrasound classification systems and SWE Emax. The diagnostic efficacy of the four ultrasound classification systems in combination with SWE were calculated and compared with those of pre-combination.

RESULTS

The ROC curves indicated that the cut-off value of ACR TI-RADS, Kwak TI-RADS, ATA guidelines, KTA/KSThR guidelines and Emax of SWE was TR5, 4c, high-suspicion, high-suspicion, and 41.7 kPa, respectively, and the area under the ROC curve (AUC) was 0.907(0.879-0.934), 0904(0.876-0.932), 0.894(0.863-0.924), 0.888(0.856-0.919), 0.886(0.859-0.913), respectively. After combination with SWE, the the sensitivities of the four ultrasound classification systems for the diagnosis of nodules were improved, and the differences were statistically significant (all P≤0.001); the specificities were decreased, but the differences were not statistically significant (all P > 0.05); the accuracies were improved, but only the difference of ACR TI-RADS was statistically significant (x2 = 4.45, P = 0.035); the differences in the AUCs were not significant (all P > 0.05).

CONCLUSIONS

The four ultrasound classification systems and SWE all had high performance in the diagnosis of thyroid nodules. The four classification systems in combination with SWE were all beneficial to the differential diagnosis of nodules, and ACR TI-RADS in combination with SWE was more effective, especially for TR3 and TR4 nodules.

Diagnostic performance of combination of ultrasound elastography and BRAF gene detection in malignant thyroid nodule: a retrospective study

OBJECTIVES

The aims of our study were to explore the preoperative diagnostic value of ultrasound elastography combined with BRAF gene detection in malignant thyroid nodule, and find whether shear wave elastography (SWE) combined with BRAF gene detection can improve the diagnostic sensitivity and specificity.

METHODS

From 1480 patients with thyroid nodule examined between January 2015 and December 2017, a retrospective analysis was performed on 161 patients who underwent thyroidectomy. Diagnosis was confirmed by postoperative pathology, including 139 malignant thyroid nodules and 22 benign thyroid nodules. All the patients underwent SWE, BRAF gene detection, and the combination for their preoperative evaluation. The sensitivities, specificities, and accuracies of SWE, BRAF gene detection, and the combination for detection of malignant thyroid nodules were calculated and then compared using Fisher's exact probability test, based on the original preoperative reports and postoperative pathology. A receiver-operating characteristic curve analysis was performed to compare the diagnostic performance of SWE, BRAF gene detection, and combination for detecting malignant thyroid nodules.

RESULTS

Based on the original preoperative reports and postoperative pathology, SWE, BRAF gene detection, and the combination showed sensitivities of 88.67%, 78.41%, 92.8%, and specificities of 72.77%, 77.27%, 95.45%. A correct diagnosis was obtained in 85.82%, 78.26%, 93.16% and missed diagnosis rates were 12.23%, 21.58%, and 7.19%. The sensitivities, specificities, and correct diagnosis rate in the combination group were significantly higher than any single detection method (P<0.05). The missed diagnosis rate in the combination group was significantly lower than any single detection method (P<0.05). The receptor operating characteristics curve analysis showed a significantly higher diagnostic performance for the combination than for SWE and BRAF gene detection (P<0.05). The interobserver agreement for detecting malignant thyroid nodule was better for the combination than for SWE or BRAF gene detection alone.

CONCLUSION

For the detection of a malignant thyroid nodule, SWE combined with BRAF gene detection was more sensitive and showed a higher diagnostic performance than SWE or BRAF gene detection alone.

Can the unnecessary operations for suspected thyroid nodules be avoided by the combined use of the strain ratio and elastography score?

Introduction

Only 5%–15% of thyroid surgical specimens are reported as malignant. Most of the operations are performed due to suspicion of malignancy as a result of fine needle aspiration biopsy but invasiveness, non-diagnostic results and potential repeat biopsies are disadvantages of fine needle aspiration biopsy.

Objective

The aim of this study was to investigate the effectiveness of simultaneously using both the strain ratio and elasticity score in the differential diagnosis of thyroid nodules, as well as to assess the compatibility of these two methods.

Methods

A total of 144 nodules were included in the study. The final histopathologic diagnosis was used as the reference standard. The area under the curve sensitivity, specificity, and cut-off values of the strain ratio and elasticity score were determined using receiver operating characteristic curve analysis. The compatibility and comparison of strain ratio and elasticity score were also performed.

Results

Twenty eight nodules (19.4%) were malignant. The strain ratio and elasticity score results were found to be significantly successful in predicting thyroid malignancy (p < 0.001 for both). Moreover, the area under the curve for the strain ratio and elasticity score were found to be 0.944 and 0.960, respectively. The diagnostic accuracy of the elasticity score was found to be superior to that of the strain ratio, but this difference was not statistically significant (p = 0.456). When the compatibility of the strain ratio and elasticity score was examined, the two evaluations were revealed to be statistically consistent with each other (Kappa = 0.767; p < 0.001). When the strain ratio and the elasticity score were used together, the specificity of capturing the correct diagnosis increased from 84.5% to 93.1%.

Conclusion

When the strain ratio an elasticity score were used together for the differential diagnosis of thyroid nodules, more accurate results were obtained. Thus, combining both methods may be a promising alternative to fine needle aspiration biopsy in order to prevent unnecessary surgical interventions for suspected thyroid nodules.