Thyroid imaging reporting and data system (TI-RADS) in the diagnostic value of thyroid nodules: a systematic review

Multitask network for thyroid nodule diagnosis based on TI-RADS

PURPOSE

Assessment of thyroid nodules is usually relied on the experience of the radiologist and is time consuming. Classification model of thyroid nodules can not only reduce the burden on physicians but also provide objective recommendations. However, most classification models based on deep learning simply give a prediction result of the benignity or malignancy of nodules thus physicians have no way of knowing how the deep learning gets the prediction result due to the black-box nature of neural networks. In this work, we integrate the explainability directly into the outputs generated by the model through combining TI-RADS. The inference process of the proposed method is consistent with doctor's clinical diagnosis process, therefore, doctors can better explain the diagnosis results of the model to the patient.

METHODS

A multitask network based on TI-RADS (MTN-TI-RADS) for the classification of thyroid nodules is proposed. In this network, a set of TI-RADS classifications of nodules is first obtained by multitask learning, then the TI-RADS points and the corresponding risk levels are calculated, finally, nodules are classified as benign and malignant. The classification process through the network is consistent with the diagnostic process of physician, thus the results of classification can be easily understood by physicians. In addition, the attention modules are introduced to the spatial and channel domains to let the network focus more on critical features.

RESULTS

To verify the classification performance of our method, we compared the results obtained through our method with the results of the radiologist's evaluation. For the 781 test nodules in the internal dataset and the 886 test nodules in the external dataset, the sensitivity and specificity of MTN-TI-RADS were 0.988, 0.912 in internal dataset, 0.949, 0.930 in external dataset, versus the senior radiologist of 0.925 (P < 0.001), 0.816 (P = 0.005) and 0.910(P = 0.009), 0.836 (P < 0.001), respectively. And the area under the receiver operating characteristic curve (AUC) of MTN-TI-RADS was 0.981 in internal dataset, 0.973 in external dataset, versus the senior radiologist of 0.905, 0.923. For the internal dataset, we also computed the accuracy of the risk level (TR1 to TR5) and the mean absolute error (MAE). The accuracy of the risk level of the proposed method is 78%, and the MAE is 1.30. The MAE of the total points (0 to 14 points) is 1.30.

CONCLUSIONS

An effective and result-interpretable end-to-end thyroid nodule classification network (MTN-TI-RADS) is proposed. MTN-TI-RADS has superior ability to classify malignant and benign thyroid nodules compared to senior radiologists. Based on MTN-TI-RADS, a classification model with strong interpretation and a high degree of physician trust is constructed. The proposed classification network is consistent with the diagnosis process of physicians, thus is more reliable and interpretable, and has great potential for clinical application. This article is protected by copyright. All rights reserved.

Diagnostic Performance of Kwak, EU, ACR, and Korean TIRADS as Well as ATA Guidelines for the Ultrasound Risk Stratification of Non-Autonomously Functioning Thyroid Nodules in a Region with Long History of Iodine Deficiency: A German Multicenter Trial

Germany has a long history of insufficient iodine supply and thyroid nodules occur in over 30% of the adult population, the vast majority of which are benign. Non-invasive diagnostics remain challenging, and ultrasound-based risk stratification systems are essential for selecting lesions requiring further clarification. However, no recommendation can yet be made about which system performs the best for iodine deficiency areas. In a German multicenter approach, 1211 thyroid nodules from 849 consecutive patients with cytological or histopathological results were enrolled. Scintigraphically hyperfunctioning lesions were excluded. Ultrasound features were prospectively recorded, and the resulting classifications according to five risk stratification systems were retrospectively determined. Observations determined 1022 benign and 189 malignant lesions. The diagnostic accuracies were 0.79, 0.78, 0.70, 0.82, and 0.79 for Kwak Thyroid Imaging Reporting and Data System (Kwak-TIRADS), American College of Radiology (ACR) TI-RADS, European Thyroid Association (EU)-TIRADS, Korean-TIRADS, and American Thyroid Association (ATA) Guidelines, respectively. Receiver Operating Curves revealed Areas under the Curve of 0.803, 0.795, 0.800, 0.805, and 0.801, respectively. According to the ATA Guidelines, 135 thyroid nodules (11.1%) could not be classified. Kwak-TIRADS, ACR TI-RADS, and Korean-TIRADS outperformed EU-TIRADS and ATA Guidelines and therefore can be primarily recommended for non-autonomously functioning lesions in areas with a history of iodine deficiency.

Reproducibility and Interobserver Agreement of Different Thyroid Imaging and Reporting Data Systems (TIRADS)

INTRODUCTION

A number of classification systems (TIRADS) have been developed to estimate the likelihood of malignancy in thyroid nodules, but their reproducibility is yet to be assessed. We evaluated the interobserver variability and diagnostic performance of the TIRADS in Kwak's modification (Kw-TIRADS) and European TIRADS (EU-TIRADS).

METHODS

Two independent specialists, blinded concerning the morphology of the nodules, evaluated ultrasound images of 153 thyroid nodules identified in 149 patients at multiple time points.

RESULTS

The interobserver agreement (Cohen's κ) was 0.52 and 0.67 for Kw-TIRADS and EU-TIRADS, respectively, and rated as substantial. There were strong correlations between Kw-TIRADS and EU-TIRADS for the two observers with Spearman's coefficients of 0.731 (p = 0.00025) and 0.661 (p = 0.0012), respectively. Sensitivity of Kw-TIRADS for the diagnosis of thyroid cancer was 95-92.31% and that of EU-TIRADS was 92.31-89.74%, with specificity of about 60% for both TIRADS.

CONCLUSION

Despite the wide variability in the description of single ultrasonographic features, both Kw-TIRADS and EU-TIRADS may be a useful diagnostic tool in clinical practice.

Ultrasonographic Findings in Common Thyroid and Parathyroid Disorders—Advantages of Real Time Observation by the Endocrinologist with their Own Ultrasound Machine

In this review we discuss the significance of the main ultrasonographic features of common thyroid and parathyroid conditions, with a focus on the advantages of real time observation. The thyroid specialist, defined as an endocrinologist with a major interest in thyroid disorders and access to a portable ultrasound machine, can correlate what they see with the thyroid blood test results and clinical findings in a way that is not available to the general endocrinologist who relies on the interpretation by the consultant radiologist of ultrasound images prepared by a technician. We also discuss the significance of the small, very bright, intra nodular microcalcifications found in benign colloid nodules, which we call “colloid spots” and the difference between these and the 3–4 mm soft microcalcifications that are 90% specific for papillary thyroid cancer and provide a new system for staging the inflammatory changes in Hashimoto thyroiditis, as observed on ultrasonography.

Hürthle cell neoplasms of the thyroid: Pathologic outcomes and ultrasonographic analysis

BACKGROUND

Fine-needle aspiration (FNA) of thyroid nodules suspicious for Hürthle cell neoplasms (HCN) have uncertain rate of malignancy. We aim to characterize rate and predictors of malignancy at our institution and compare these findings with established literature to help guide management.

METHODS

Single tertiary-referral center, retrospective study of 166 adults who underwent hemithyroidectomy or total thyroidectomy following FNA suspicious for HCN from 1998-2018. Demographic information and surgical histopathologic results were collected. Preoperative ultrasonography was independently scored on the American College of Radiology Thyroid Imaging Reporting and Data System (TI-RADS) by a board-certified head and neck radiologist.

RESULTS

There were 39 males and 127 females. Overall, 25 (15.1%) patients had carcinoma, with 15 (9%) being Hürthle cell carcinoma (HCC). Men had higher incidence of carcinoma (25.6% v. 11.8%, P = .035), and especially older males. Contralateral carcinoma was seen in 3 of 13 (23.1%) patients that underwent completion thyroidectomy. Patients with carcinoma had larger nodules (average diameter 3.3 cm versus 2.5 cm, respectively, P = .01), but no association with TI-RADS.

CONCLUSION

Adults with nodules suspicious for HCN have significant risk of malignancy consistent with prior studies. Older males and larger nodule diameter are associated with malignancy in this cohort, but TI-RADS grade is not. These findings provide a framework for management and counseling for lesions suspicious for HCN.

COMPARISON OF DIAGNOSTIC PERFORMANCE BETWEEN THE AMERICAN COLLEGE OF RADIOLOGY THYROID IMAGING REPORTING AND DATA SYSTEM AND AMERICAN THYROID ASSOCIATION GUIDELINES: A SYSTEMATIC REVIEW

Objective: We aimed to compare the diagnostic accuracy of the American College of Radiology Thyroid Imaging Reporting and Data System (ACR TI-RADS) with the American Thyroid Association (ATA) guidelines in risk stratification of thyroid nodules. Methods: We performed a computerized search of Medline, EMBASE, Web of Science, Cochrane Library, and Google Scholar to identify eligible articles published before July 31, 2019. We included studies providing head-to-head comparison between ACR TI-RADS and ATA guidelines, with fine-needle aspiration biopsy cytology results or pathology results as the reference standard. Quality assessment of included studies was conducted using the Quality Assessment of Diagnostic Accuracy Studies-2 tool. Summary estimates of sensitivity and specificity were calculated by bivariate modeling and hierarchical summary receiver operating characteristic modeling. We also performed multiple subgroup analyses and meta-regression. Results: Twelve original articles with 13,000 patients were included, involving a total of 14,867 thyroid nodules. The pooled sensitivity of ACR TI-RADS and ATA guidelines was 0.84 (95% confidence interval [CI], 0.76-0.89) and 0.89 (95% CI, 0.80-0.95), with specificity of 0.67 (95% CI, 0.56-0.76) and 0.46 (95% CI, 0.29-0.63), respectively. There were no significant differences between the two classification criteria in terms of both sensitivity (P = .26) and specificity (P = .05). For five studies providing direct comparison of ACR TI-RADS, ATA guidelines, and Korean TI-RADS, our analyses showed that the Korean TI-RADS yielded the highest sensitivity (0.89; 95% CI, 0.82-0.94), but at the cost of a significant decline in specificity (0.23; 95% CI, 0.17-0.30). Conclusion: Both classification criteria demonstrated favorable sensitivity and moderate specificity in the stratification of thyroid nodules. However, use of ACR TI-RADS could avoid a large number of biopsies at the cost of only a slight decrease in sensitivity. Abbreviations: ACR = American College of Radiology; ATA = American Thyroid Association; FNAB = fine-needle aspiration biopsy; HSROC = hierarchical summary receiver operating characteristic; SROC = summary receiver operating characteristic; TI-RADS = Thyroid Imaging Reporting and Data System; US = ultrasonography.

Advanced Ultrasound Application - Impact on Presurgical Risk Stratification of the Thyroid Nodules

Aim

Current major guidelines recommend risk stratification of the thyroid nodules, after each diagnostic evaluation, in order to focus attention on potentially risky nodules. The main aim of our study was to evaluate the performance of combined advanced ultrasound techniques in this process, compared with conventional stratification models, in order to reduce unnecessary fine-needle biopsies, respectively, surgery.

Material and Methods

We evaluated 261 cases (261 nodules) using conventional ultrasound (2B), real-time Doppler evaluation (4D) respectively, real-time elastography, using a linear multifrequency probe and a linear volumetric probe (Hitachi Prerius Machine, Hitachi Inc, Japan). All the nodules were classified using a risk stratification model comprising seven conventional US characteristics, two 4 D characteristics and a color map RTE aspect. The results were compared with the pathology results, considered the golden standard diagnosis.

Results

The prevalence of malignant nodules was 21.83% (57 cases). Conventional risk classification generated: 106 low-risk cases, 113 intermediate-risk and 42 high-risk cases. Our proposed risk classification changes the conventional risk classification with a risk upgrade in 27 cases and with a risk downgrade in 69 cases. The diagnostic quality of the combined risk stratification model was better, considering a low-risk category predictive for benignancy and a high category predictive for malignancy: Sensitivity: 80.88% versus 49.01%, respectively, Specificity: 91.22% versus 54.38. The diagnostic power differences were observed regardless of the nodule size.

Conclusion

Advanced ultrasound techniques did add diagnostic value in the presurgical risk assessment of the thyroid nodules.

Clinical diagnostic value of contrast-enhanced ultrasound and TI-RADS classification for benign and malignant thyroid tumors: One comparative cohort study

To evaluate the diagnostic efficacy and clinical value of contrast-enhanced ultrasonography (CEUS) plus TI-RADS classification in benign and malignant thyroid tumors compared with either method alone.The informed consent was signed all patients. A total of 370 patients with thyroid tumors of TI-RADS category 3 and 4 were recruited, with 432 thyroid nodules. They respectively received routine ultrasonography and CEUS. The nodules were reclassified according to CEUS scoring, and a combined diagnosis was made. The pathological results were taken as the gold standard. The sensitivity (Se), specificity (Sp), positive predictive value (PPV), negative predictive value (NPV) and area under the ROC curve were calculated for the 3 diagnostic methods. The diagnostic efficacy was compared by using Student t test, Pearson chi-square (χ) test, McNemar chi-square (χ) test or Z test. Student t test and logistic regression were employed for comparing different imaging features of benign and malignant thyroid tumors on CEUS and risk analysis.Of 432 thyroid nodules, there were 258 malignant nodules (59.72%) and 174 benign ones (40.28%). By logistic regression, 6 suspicious features on CEUS were considered significant for differentiating malignant from benign tumors: slow entry of contrast agents during enhancement stage (OR = 15.610, P = .001), slow time to peak (OR = 7.416, P = .002), non-uniform enhancement (OR = 10.076, P = .023), enhancement pattern (irregular) (OR = 36.233, P = .002), enhancement boundary (unclear) (OR = 25.300, P = .012), and no ring-like enhancement (OR = 25.297, P = .004). CEUS plus TI-RADS classification showed a higher diagnostic efficacy for differentiating between benign and malignant thyroid tumors. The Se was 85.66% (0.806-0.896), Sp 83.33% (0.768-0.884), PPV 88.40% (0.836-0.919), NPV 79.67% (0.729-0.851), and AUC 0.867 ± 0.019 (0.815-0.889). The above indicators were of statistical significance as compared with TI-RADS classification or CEUS alone (P <.05).CEUS can more clearly visualize microvascular distribution of the nodules and offers a new approach to diagnose benign and malignant thyroid tumors. TI-RADS classification plus CEUS is more accurate than TI-RADS classification alone. This combined approach is worthy of clinical popularization.

Combination of ultrasound elastography with TI-RADS in the diagnosis of small thyroid nodules (≤10 mm): A new method to increase the diagnostic performance

OBJECTIVE

To evaluate the diagnostic performance of a new method of combined ultrasound elastography (UE) and thyroid imaging-reporting and data system (TI-RADS) in the differential diagnosis of small thyroid nodules.

METHODS

Ultrasonography(US), TI-RADS, Elasticity Imaging (EI), Virtual Touch Tissue Imaging (VTI) and Virtual Touch Tissue Quantification (VTQ) features of 142 thyroid nodules (maximum diameter ≤10 mm according to conventional ultrasound measurement) confirmed by surgery or FNA were retrospectively analyzed. Different elastographic methods in small benign and malignant thyroid nodules were compared. The diagnostic efficiency of three adjustment methods of conventional ultrasound TI-RADS classification and ultrasound elastography (VTI and/or VTQ) were compared.

RESULTS

The pathological examination showed that 70 thyroid nodules were benign and 72 were malignant. The differential ability of UE to diagnose the small benign and malignant thyroid nodules alone is not better than that of conventional ultrasound TI-RADS classification. The sensitivity of conventional ultrasound TI-RADS classification were higher than that of VTI and equal to VTQ(91.67% vs83.33%、91.67%), while the specificity of VTI was much higher than that of TI-RADS and VTQ(91.43% vs 75.71%、60.00%). The diagnostic sensitivity and specificity of TI-RADS classification plus UE (VTI + VTQ) were 94.44% and 87.14% respectively. TI-RADS classification combined with UE (VTI + VTQ) was the highest diagnostic efficiency.

CONCLUSION

Conventional ultrasound TI-RADS classification is the basis for the diagnosis of small thyroid nodules. The combination of TI-RADS with VTI and VTQ can significantly improve the differential diagnosis of small benign and malignant thyroid nodules. It may provide a new and reliable method for the clinical diagnosis of small thyroid nodules.

Effect of Implementing Community of Practice Modified Thyroid Imaging Reporting and Data System on Reporting Adherence and Number of Thyroid Biopsies

RATIONALE AND OBJECTIVES

Thyroid nodules are common in the population, although the rate of malignancy is relatively low (5%-15%). The purpose of this study was to determine if introducing a modified standardized reporting format and management algorithm (Thyroid Imaging Reporting and Data System [TI-RADS]) affects radiologist reporting adherence, number of thyroid biopsies, and other measurable outcomes.

MATERIALS AND METHODS

All thyroid biopsies performed over two 6-month periods were evaluated at a tertiary care hospital with Research Ethics Board approval. The first period was before implementation of TI-RADS and the second was several months after implementation of TI-RADS (using a modified version made through a multidisciplinary collaboration). The number of biopsies performed was determined in each of the two periods as well as the percent of positive malignancy, wait times, and rates of non-diagnostic/unsatisfactory and inconclusive biopsies, which included atypia of undetermined significance (AUS) and follicular lesion of undetermined significance (FLUS).

RESULTS

The average number of biopsies performed prior to implementing modified Kwak's TI-RADS was 74 thyroid biopsies per month and the average number of diagnostic ultrasounds was 271. After the introduction of modified Kwak's TI-RADS, the average number of thyroid biopsies decreased to 60 per month (an 18.9% reduction, P < .05), and the number of diagnostic ultrasound increased to 287 per month (a 5.9% increase from 2016 to 2017). The average wait time for a thyroid biopsy decreased from 5 to 3 weeks (P < .05). There was a slight increase in the rate of positive malignancy results (from 15% to 18%), although it was not statistically significant. The rate of non-diagnostic/unsatisfactory and inconclusive results (including AUS and FLUS) remained unchanged (18% AUS/FLUS/15% non-diagnostic/unsatisfactory before and 17% AUS/FLUS/15% non-diagnostic/unsatisfactory after TI-RADS introduction, P > .05).

CONCLUSIONS

Introduction of a multidisciplinary-approved standardized reporting system with evidence-based management recommendations led to no statistically significant change in the number of diagnostic ultrasounds but a statistically significant reduction in the number of monthly thyroid biopsies and associated reduction in wait times.

Use of the Kwak Thyroid Image Reporting and Data System (K-TIRADS) in differential diagnosis of thyroid nodules: systematic review and meta-analysis

PURPOSE

The purpose of this systematic literature review was to assess the usefulness of the Thyroid Image Reporting and Data System (K-TIRADS) classification proposed by Kwak for differentiation of thyroid nodules.

MATERIAL AND METHODS

Four literature databases were searched for relevant articles through early January 2017. A meta-analysis was performed to calculate pooled sensitivity, specificity, positive likelihood ratio (LR+), negative likelihood ratio (LR-) and diagnostic odds ratio (DOR). The area under the curve (AUC) from the pooled receiver operating characteristic (ROC) was used to assess the usefulness of this classification for differentiation of thyroid nodules. Meta-analysis was conducted by using meta-analysis software.

RESULTS

We analysed six publications describing 10,926 nodules. Pooled sensitivity, specificity, LR+, LR-, DOR, and AUC for pooled ROC were 0.983 (95 % CI 0.976-0.989), 0.552 (95 % CI 0.542-0.562), 2.666 (95 % CI 1.692-4.198), 0.05 (95 % CI 0.035-0.072), 51.020 (95 % CI 15.241-170.79) and 0.938, respectively.

CONCLUSIONS

Kwak TIRADS has high sensitivity and low specificity. Thus, it is very useful to discard the benign cases and to reduce the number of biopsies.

KEY POINTS

• Routine, adequate standardization of thyroid nodules ultrasound classification is mandatory. • Kwak TIRADS parameters are accurate for differentiating focal thyroid lesions. • Kwak TIRADS system is simple to apply. • Kwak TIRADS system may become a useful diagnostic tool.

Ultrasound features of extranodal extension in the metastatic cervical lymph nodes of papillary thyroid cancer: a case-control study

Objective:

Extranodal extension in cervical lymph nodes is an important risk factor for the progression and prognosis of papillary thyroid cancer. The purpose of this study was to identify the common and characteristic preoperative ultrasonography features that are associated with the pathologic extranodal extension of metastatic papillary thyroid carcinoma.

Methods:

We retrospectively assessed and compared clinicopathologic and ultrasound features between 60 papillary thyroid cancer patients with extranodal extension and 120 control patients with papillary thyroid cancer without extranodal extension.

Results:

With respect to the pathological N stage and clinicopathologic features, N1b stage papillary thyroid carcinomas were more frequently found in patients who were extranodal extension-positive, in comparison with those who were extranodal extension-negative (78.3% vs. 63.3%, P=0.043). Extranodal extension was detected most frequently in level VI cervical lymph nodes (48.7%). In our univariate analysis of patients with papillary thyroid carcinoma, cervical lymph nodes with extranodal extension showed higher incidences of node matting, microcalcification, cystic area, aspect ratio <2, and larger diameter than those without extranodal extension (all P<0.05). Our multivariate analysis demonstrated that node matting and cystic area were independent risk factors for the presence of extranodal extension [odds ratio (OR): 4.751, 95% confidence interval (CI): 1.212~18.626, P=0.025; OR: 2.707, 95% CI: 1.127~6.502, P=0.026].

Conclusions:

Common ultrasound features may indicate the presence of extranodal extension in patients with metastatic cervical lymph nodes of papillary thyroid carcinoma.

Ultrasonography-Based Classification and Reporting System for the Malignant Risk of Thyroid Nodules

OBJECTIVE

The aim of this study was to test the predictive value of a Thyroid Imaging Reporting and Data System (TI-RADS) for malignant thyroid nodules.

METHODS

Ultrasonographic data was examined for 910 thyroid nodules with histopathologically confirmed diagnoses. Nodules were placed into incomplete (category 0) or complete final categories (1, 2, 3a, 3b, 3c, 4, or 5) based on the presence and number of ultrasonographic features of malignancy, and the predictive value for the malignancy of nodules in categories 2-4 was assessed.

RESULTS

The overall rate of malignancy among thyroid nodules included in the study was 59.34%. The rate of malignancy gradually increased according to TI-RADS categories as follows: category 2, 5.4%; category 3 (a-c), 36% to 92%; and category 4, 99.0%. When nodules of category 2 were counted as benign, the reliability of the TI-RADS classification for determining the risk of malignancy was as follows; sensitivity, 98.15%; specificity, 47.84%; positive predictive value, 73.31%; negative predictive value, 94.65%; and odds ratio, 48.61.

CONCLUSIONS

The TI-RADS classification used in this study is relatively simple and provides a reliable measure of the risk of malignancy of thyroid nodules.

Systematic reviews of diagnostic tests in endocrinology: an audit of methods, reporting, and performance

BACKGROUND

Systematic reviews provide clinicians and policymakers estimates of diagnostic test accuracy and their usefulness in clinical practice. We identified all available systematic reviews of diagnosis in endocrinology, summarized the diagnostic accuracy of the tests included, and assessed the credibility and clinical usefulness of the methods and reporting.

METHODS

We searched Ovid MEDLINE, EMBASE, and Cochrane CENTRAL from inception to December 2015 for systematic reviews and meta-analyses reporting accuracy measures of diagnostic tests in endocrinology. Experienced reviewers independently screened for eligible studies and collected data. We summarized the results, methods, and reporting of the reviews. We performed subgroup analyses to categorize diagnostic tests as most useful based on their accuracy.

RESULTS

We identified 84 systematic reviews; half of the tests included were classified as helpful when positive, one-fourth as helpful when negative. Most authors adequately reported how studies were identified and selected and how their trustworthiness (risk of bias) was judged. Only one in three reviews, however, reported an overall judgment about trustworthiness and one in five reported using adequate meta-analytic methods. One in four reported contacting authors for further information and about half included only patients with diagnostic uncertainty.

CONCLUSION

Up to half of the diagnostic endocrine tests in which the likelihood ratio was calculated or provided are likely to be helpful in practice when positive as are one-quarter when negative. Most diagnostic systematic reviews in endocrine lack methodological rigor, protection against bias, and offer limited credibility. Substantial efforts, therefore, seem necessary to improve the quality of diagnostic systematic reviews in endocrinology.

Multivariate evaluation of Thyroid Imaging Reporting and Data System (TI-RADS) in diagnosis malignant thyroid nodule: application to PCA and PLS-DA analysis

OBJECTIVE

To explore the significance of ultrasonic features in differential diagnosis of thyroid nodules via combining the thyroid imaging reporting and data system (TI-RADS) and multivariate statistical analysis.

METHODS

Patients who received surgical treatment and was diagnosed with single thyroid nodule by postoperative pathology and preoperative ultrasound were enrolled in this study. Multivariate analysis was applied to assess the significant ultrasonic features which correlated with identifying benign or malignance and grading the TI-RADS classification of thyroid nodule.

RESULTS

There were significant differences in the nodule size, aspect ratio, internal, echogenicity, boundary, presence or absence of calcifications, calcification type and CDFI between benign and malignant thyroid nodules. Multivariate analysis showed clear-cut distinction both between benign and malignance and among different TI-RADS categories of malignancy nodules. The shape and calcification of the nodule were important factors for distinguish the benign and malignance. Height of the nodule, aspect and calcification was important factors for grading TI-RADS categories of malignancy thyroid nodules.

CONCLUSIONS

Ill-defined boundary, irregular shape and presence of calcification related with highly malignant risk for thyroid nodule. The larger height and aspect and presence of calcification related with higher TI-RADS classification of malignancy thyroid nodule.

Application of high-resolution ultrasound, real-time elastography, and contrast-enhanced ultrasound in differentiating solid thyroid nodules

High-resolution ultrasound (HRUS) is a sensitive tool for identifying thyroid nodules. Real-time elastography (RTE) and contrast-enhanced ultrasound (CEUS) are newly developed methods which could measure tissue elasticity and perfusion features. The aim of the present study was to evaluate and compare the diagnostic efficiency of HRUS, RTE, CEUS and their combined use in the differentiation of benign and malignant solid thyroid nodules.In total, 111 consecutive patients with 145 thyroid nodules who were scheduled for surgery were included in the study. All of them underwent HRUS, RTE, and CEUS examination. The independent ultrasound (US) predictors for malignancy were determined and quantified using logistic regression analysis, based on which a risk-scoring model was established for each method. The diagnostic efficiency of each method was assessed by receiver operating characteristic (ROC) curve analysis.HRUS showed the best diagnostic efficiency among the 3 US methods, with 74.6% sensitivity and 87.8% specificity. CEUS had higher sensitivity (85.7%), whereas RTE alone did not show much advantage. Combined use of RTE and HRUS increased the sensitivity (92.1%). The HRUS-RTE-CEUS combination could increase both the sensitivity and specificity (87.3%, 91.5%), with the best AUC (0.935) among all the methods.The overall diagnostic value of HRUS in predicting malignancy is the best among the 3 US methods. Combined use of RTE and CEUS and HRUS could improve the diagnostic efficiency for solid thyroid nodules.

Diagnostic Value of Conventional Ultrasonography Combined with Contrast-Enhanced Ultrasonography in Thyroid Imaging Reporting and Data System (TI-RADS) 3 and 4 Thyroid Micronodules

BACKGROUND The present study was conducted to investigate the diagnostic performance of conventional ultrasonography (US) combined with contrast-enhanced ultrasonography (CEUS) in thyroid micronodules with thyroid imaging reporting and data system (TI-RADS) category 3 and 4. MATERIAL AND METHODS The features of conventional US and CEUS ion 102 case of thyroid micronodule samples, which were diagnosed based on pathological and clinical examination, were retrospectively analyzed. Logistic regression analysis was used to analyze the diagnostic accuracy in malignant thyroid micronodules. Receiver operator characteristic (ROC) curve was used to assess the performance of those 2 technologies. RESULTS A significant difference in age was found between the benign and malignant groups. The benign and malignant groups showed significant differences in shape, margin, aspect ratio (A/T) ≥1, microcalcification, suspicious lymph gland, enhancement time, enhancement pattern, enhancement intensity, nodule sizes, enhancement margins, and rim-like enhancement. Logistic regression analysis of conventional US showed that A/T ≥1, irregular shape, microcalcification, and suspicious lymph glands are risk factors for thyroid micronodules, while logistic regression analysis of CEUS showed that slow enhancement time and absence of rim-like enhancement are risk factors for thyroid micronodules. Logistic regression analysis of conventional US combined with CEUS demonstrated that A/T ≥1, microcalcification, suspicious lymph gland, slow enhancement time, and absence with rim-like enhancement are risk factors. The ROC curve for conventional US, CEUS, and conventional US combined with CEUS were 90.0%, 90.7%, 99.0%, respectively. CONCLUSIONS Our results show that conventional US combined with CEUS had superior diagnostic performance for TI-RADS 3 and 4 thyroid micronodules compared with conventional US and CEUS alone.

Value of TIRADS, BSRTC and FNA-BRAF V600E mutation analysis in differentiating high-risk thyroid nodules

The thyroid imaging reporting and data system (TIRADS) and Bethesda system for reporting thyroid cytopathology (BSRTC) have been used for interpretation of ultrasound and fine-needle aspiration cytology (FNAC) results of thyroid nodules. BRAF(V600E) mutation analysis is a molecular tool in diagnosing thyroid carcinoma. Our objective was to compare the diagnostic value of these methods in differentiating high-risk thyroid nodules. Total 220 patients with high-risk thyroid nodules were recruited in this prospective study. They all underwent ultrasound, FNAC and BRAF(V600E) mutation analysis. The sensitivity and specificity of TIRADS were 73.1% and 88.4%. BSRTC had higher specificity (97.7%) and similar sensitivity (77.6%) compared with TIRADS. The sensitivity and specificity of BRAF(V600E) mutation (85.1%, 100%) were the highest. The combination of BSRTC and BRAF(V600E) mutation analysis significantly increased the efficiency, with 97.8% sensitivity, 97.7% specificity. In patients with BSRTC I-III, the mutation rate of BRAF(V600E) was 64.5% in nodules with TIRADS 4B compared with 8.4% in nodules with TIRADS 3 or 4A (P < 0.001). Our study indicated that combination of BSRTC and BRAF(V600E) mutation analysis bears a great value in differentiating high-risk thyroid nodules. The TIRADS is useful in selecting high-risk patients for FNAB and patients with BSRTC I-III for BRAF(V600E) mutation analysis.

Thyroid nodule ultrasound: technical advances and future horizons

Thyroid nodules are extremely common and the vast majority are non-malignant; therefore the accurate discrimination of a benign lesion from malignancy is challenging. Ultrasound (US) characterisation has become the key component of many thyroid nodule guidelines and is primarily based on the detection of key features by high-resolution US. The thyroid imager should be familiar with the strengths and limitations of this modality and understand the technical factors that create and alter the imaging characteristics. Specific advances in high-resolution US are discussed with reference to individual features of thyroid cancer and benign disease. Potential roles for three-dimensional thyroid ultrasound and computer-aided diagnosis are also considered. The second section provides an overview of current evidence regarding thyroid ultrasound elastography (USE). USE is a novel imaging technique that quantifies tissue elasticity (stiffness) non-invasively and has potential utility because cancers cause tissue stiffening. In recent years, there has been much research into the value of thyroid USE for distinguishing benign and malignant nodules. Preliminary findings from multiple pilot studies and meta-analyses are promising and suggest that USE can augment the anatomical detail provided by high-resolution US. However, a definite role remains controversial and is discussed.

TEACHING POINTS

• High-resolution US characterises thyroid nodules by demonstration of specific anatomical features • Technical advances heavily influence the key US features of thyroid nodules • Most papillary carcinomas appear stiffer than benign thyroid nodules on US elastography (USE) • Thyroid USE is controversial because of variation in the reported accuracies for malignancy • Combined grey-scale US/USE may lower the FNAC rate in benign nodules.