Quantitative evaluation of contrast-enhanced ultrasound after intravenous administration of a microbubble contrast agent for differentiation of benign and malignant thyroid nodules: assessment of diagnostic accuracy

Detection of malignant lesions in cytologically indeterminate thyroid nodules using a dual-layer spectral detector CT-clinical nomogram

Purpose

To evaluate the capability of dual-layer detector spectral CT (DLCT) quantitative parameters in conjunction with clinical variables to detect malignant lesions in cytologically indeterminate thyroid nodules (TNs).

Materials and methods

Data from 107 patients with cytologically indeterminate TNs who underwent DLCT scans were retrospectively reviewed and randomly divided into training and validation sets (7:3 ratio). DLCT quantitative parameters (iodine concentration (IC), NICP (IC nodule/IC thyroid parenchyma), NICA (IC nodule/IC ipsilateral carotid artery), attenuation on the slope of spectral HU curve and effective atomic number), along with clinical variables, were compared between benign and malignant cohorts through univariate analysis. Multivariable logistic regression analysis was employed to identify independent predictors which were used to construct the clinical model, DLCT model, and combined model. A nomogram was formulated based on optimal performing model, and its performance was assessed using receiver operating characteristic curve, calibration curve, and decision curve analysis. The nomogram was subsequently tested in the validation set.

Results

Independent predictors associated with malignant TNs with indeterminate cytology included NICP in the arterial phase, Hashimoto's Thyroiditis (HT), and BRAF V600E (all p < 0.05). The DLCT-clinical nomogram, incorporating the aforementioned variables, exhibited superior performance than the clinical model or DLCT model in both training set (AUC: 0.875 vs 0.792 vs 0.824) and validation set (AUC: 0.874 vs 0.792 vs 0.779). The DLCT-clinical nomogram demonstrated satisfactory calibration and clinical utility in both training set and validation set.

Conclusion

The DLCT-clinical nomogram emerges as an effective tool to detect malignant lesions in cytologically indeterminate TNs.

Diagnostic value of qualitative and quantitative parameters of contrast-enhanced ultrasound for differentiating differentiated thyroid carcinomas from benign nodules

Objective

To explore the diagnostic value of contrast-enhanced ultrasound (CEUS) of qualitative and quantitative parameters for differentiating differentiated thyroid cancers from benign nodules.

Method

A total of 290 thyroid nodules that were pathologically confirmed were enrolled in this study. The univariate analysis was performed for the clinical characteristics and CEUS qualitative and quantitative parameters of the inside and peripheral zone of nodules, including age, gender, nodule size, intensity of enhancement, homogeneity, wash-in and wash-out patterns, margin after CEUS, ring enhancement, peak intensity, sharpness, time to peak(TP), and area under the curve(AUC), and the meaningful indicators in the single-factor analysis were further included in multivariate logistic regression analysis.

Results

Multivariate analysis showed that there were significant differences in age (p=0.031), nodule size (p<0.001), heterogeneous enhancement (p<0.001), hypo-enhancement (p=0.001), unclear margin after CEUS(p=0.007), inside peak (p<0.001), and outside sharpness(p<0.001) between benign and malignant nodules. However, there were no significant differences in gender, ring enhancement, wash-in, wash-out, outside TP, outside AUC between benign and malignant thyroid nodules (P>0.05, for all).

Conclusion

CEUS might be useful in the differential diagnosis of differentiated thyroid cancers and benign nodules, which could provide a certain basis for clinical treatment.

VueBox® perfusion analysis of dynamic contrast enhanced ultrasound provides added value in the diagnosis of small thyroid nodules

OBJECTIVES

To explore the potential added value of dynamic contrast enhanced ultrasound (DCE-US) using VueBox® software for the diagnosis of small solid thyroid nodules (≤1.0 cm).

PATIENTS AND METHODS

This prospective study was approved by the institutional review board and it was performed at two hospitals from January 2020 to October 2020. B mode ultrasound and contrast enhanced ultrasound (CEUS) images were obtained for 79 small solid thyroid nodules (≤1.0 cm) confirmed by ultrasound-guided fine needle aspiration cytology results in 79 consecutive patients (55 women and 24 men, median age: 41 years). The CEUS time-intensity curves (TICs) of thyroid nodules and surrounding parenchyma were created by VueBox® software (Bracco, Italy). The CEUS quantitative parameters were obtained after curve fitting. The diagnostic efficiency of the diagnostic performance of CEUS and DCE-US was evaluated and compared. The weighted kappa statistic (κ) was performed to assess the interobserver agreement and consistency between the diagnosis of CEUS and DCE-US.

RESULTS

Among the 79 thyroid nodules, 56 (70.9 %) were malignant and 23 (29.1 %) were benign lesions. Hypoenhancement during the arterial phase of CEUS was associated with malignancy (P <  0.001), with an AUC of 0.705 (sensitivity 71.4 %, specificity 69.6 %). Among all CEUS quantitative parameters, the peak enhancement (PE), wash-in rate (WiR), and wash-out rate (WoR) of DCE-US in malignancies were significantly lower than those in benign nodules (P = 0.049, P = 0.046, and P = 0.020, respectively). The AUCs of PE, WiR, and WoR were 0.642 (sensitivity 65.2 %, specificity 67.9 %), 0.643 (sensitivity 43.5 %, specificity 91.1 %), and 0.667 (sensitivity 69.6 %, specificity 69.6 %) in differentiation between benign and malignant small solid thyroid nodules (≤1.0 cm), respectively. Comparing the quantitative parameters of DCE-US between small solid thyroid nodules and surrounding normal thyroid parenchyma, the PE, WiAUC, WiR, WiPI, WoAUC, WiWoAUC, and WoR of the nodules were significantly lower than those of normal thyroid tissue (P = 0.008, P <  0.001, P = 0.037, P = 0.009, P = 0.003, P = 0.002, P = 0.049, respectively). A total of 16 (20.3 %) nodules showed isoenhancement during the arterial phase of CEUS, while the median PE ratio of surrounding tissue and thyroid nodules was 1.70 (IQR: 1.33-1.89).

CONCLUSIONS

VueBox® is a helpful tool for the evaluation of dynamic microvascularization of thyroid nodules, and DCE-US using VueBox® perfusion analysis could provide added values for differential diagnosis of small solid thyroid nodules (≤1.0 cm).

Contrast-Enhanced Ultrasonography for Differential Diagnosis of Benign and Malignant Thyroid Lesions: Single-Institutional Prospective Study of Qualitative and Quantitative CEUS Characteristics

Objectives

To extend and revise the diagnostic value of contrast-enhanced ultrasonography (CEUS) for differentiation between malignant and benign thyroid nodules.

Methods

This single-institution prospective study aims to compare CEUS qualitative and objective quantitative parameters in benign and malignant thyroid nodules. Consecutive cohort of 100 patients was examined by CEUS, 68 out of them were further analysed in detail. All included patients underwent cytological and/or histopathological verification of the diagnosis.

Results

Fifty-five (81%) thyroid nodules were benign, and 13 (19%) were malignant. Ring enhancement pattern was strongly associated with a benign aetiology (positive predictive value 100%) and heterogeneous enhancement pattern with malignant aetiology (positive predictive value 72.7%). The shape of the TIC (time-intensity curve) was more often identical in the benign lesion (98.2%) than in malignant lesions (69.2%), p=0.004.

Conclusions

This study indicates that CEUS enhancement patterns were significantly different in benign and malignant lesions. Ring enhancement was a very strong indicator of benign lesions, whereas heterogeneous enhancement was valuable to detect malignant lesions.

Benefits of Contrast-Enhanced Ultrasonography to the Differential Diagnosis of TI-RADS 4-5 Thyroid Nodules

Objective

The early detection, diagnosis, and treatment of thyroid cancer are of great significance to the prognosis for patients. This study was aimed at exploring the benefits of contrast-enhanced ultrasonography (CEUS) to the differential diagnosis of thyroid nodules classified as TI-RADS class 4 or 5.

Method

A total of 46 patients with TI-RADS 4-5 thyroid nodules admitted in Peking University People's Hospital from January 2019 to January 2021 were selected to study. The sensitivity, specificity, accuracy, and positive and negative predictive values of conventional ultrasonography (US) and conventional ultrasonography combined with contrast-enhanced ultrasonography (US + CEUS) in the diagnosis of benign and malignant thyroid nodules were compared by referring to the results of the surgical pathology report, which is seen as the "gold standard" for diagnosis, followed by the construction of receiver operating characteristic curves (ROCs).

Result

Among 57 thyroid nodules, there were statistically significant differences between benign and malignant thyroid nodules in terms of echogenicity, margin characteristics, aspect ratio, and calcification (P < 0.01). In the case of CEUS, there was no statistically significant difference among contrast agent perfusion patterns in distinguishing between benign and malignant thyroid nodules (P > 0.05). However, there were statistically significant differences among different enhancement degrees, enhanced borders, and enhancement patterns. By comparing the CEUS results of TI-RADS 4-5 thyroid nodules with the results of pathology report, the malignancy rate was found to pathology report results, the malignancy rate was 53.85% in TI-RADS class 4 thyroid nodules and 100.00% in TI-RADS class 5 thyroid nodules. Among thyroid nodules diagnosed using US, 6 benign nodules were misdiagnosed as malignant and 7 malignant nodules were misdiagnosed as benign. Among those diagnosed using US + CEUS, 2 benign nodules were misdiagnosed as malignant and 2 malignant nodules were misdiagnosed as benign. The sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of UN + CEUS significantly outperformed those of UN alone in diagnosing thyroid nodules (P < 0.05). The ROC curve analysis showed that the area under the curve (AUC) derived from US + CEUS was 0.849, while the AUC from US was only 0.726.

Conclusion

Using US + CEUS to diagnose thyroid nodules classified as TI-RADS category 4 or 5 can further improve distinguishing between benign and malignant nodules. The CEUS is of important value to clinical applications as it can provide effective supplementary information and quantitative analysis for the differentiation between benign and malignant thyroid nodules.

Four-quadrant fast compressive tracking of breast ultrasound videos for computer-aided response evaluation of neoadjuvant chemotherapy in mice

BACKGROUND AND OBJECTIVE

Neoadjuvant chemotherapy (NAC) is a valuable treatment approach for locally advanced breast cancer. Contrast-enhanced ultrasound (CEUS) potentially enables the assessment of therapeutic response to NAC. In order to evaluate the response accurately, quantitatively and objectively, a method that can effectively compensate motions of breast cancer in CEUS videos is urgently needed.

METHODS

We proposed the four-quadrant fast compressive tracking (FQFCT) approach to automatically perform CEUS video tracking and compensation for mice undergoing NAC. The FQFCT divided a tracking window into four smaller windows at four quadrants of a breast lesion and formulated the tracking at each quadrant as a binary classification task. After the FQFCT of breast cancer videos, the quantitative features of CEUS including the mean transit time (MTT) were computed. All mice showed a pathological response to NAC. The features between pre- (day 1) and post-treatment (day 3 and day 5) in these responders were statistically compared.

RESULTS

When we tracked the CEUS videos of mice with the FQFCT, the average tracking error of FQFCT was 0.65 mm, reduced by 46.72% compared with the classic fast compressive tracking method (1.22 mm). After compensation with the FQFCT, the MTT on day 5 of the NAC was significantly different from the MTT before NAC (day 1) (p = 0.013).

CONCLUSIONS

The FQFCT improves the accuracy of CEUS video tracking and contributes to the computer-aided response evaluation of NAC for breast cancer in mice.

The value of contrast-enhanced ultrasound for the diagnosis of metastatic cervical lymph nodes of papillary thyroid carcinoma: A systematic review and meta-analysis

To investigate the diagnostic efficiency of contrast-enhanced ultrasound (CEUS) for the diagnosis of cervical lymph nodes metastasis (CLNM) of papillary thyroid carcinoma (PTC), eight available datasets of seven qualified articles before March 31, 2021 were included after a comprehensive search. Meta-analysis results showed that CEUS demonstrated acceptable diagnostic performance in the diagnosis of CLNM of PTC. Furthermore, meta-regression analysis was conducted to identify the reasons for heterogeneity and the results indicated that the criteria of CEUS for the diagnosis of CLNM in PTC need to be unified.

Contrast-Enhanced Ultrasound: An Effective Method for Noninvasive Diagnosis of Mummified Thyroid Nodules

Mummified thyroid nodules are a special type of thyroid nodule, which is benign, but is often diagnosed as malignant by ultrasound. This study investigated the usefulness of contrast-enhanced ultrasound (CEUS) in the diagnosis of mummified nodules. 66 patients with mummified nodules were divided into two groups: a no-enhancement group and a low-enhancement group. 32 patients with papillary thyroid carcinoma (PTC) were recruited in control group. In the no-enhancement group, CEUS showed that there was no contrast agent entering the nodules, with or without a little dot enhancement or regular ring enhancement around the nodules. The low-enhancement group showed low enhancement inside nodules, which was similar to that in the PTC group. In semiquantitative time-intensity curve analyses, intensity maximum of the central area of nodules in the low-enhancement group was lower than that in the PTC group (P < 0.05) and time to peak of the central area of nodules in the low-enhancement group was lower than that in the PTC group (P < 0.05). The results demonstrate that CEUS could be used to effectively diagnose mummified nodules, obviating the need for patients to undergo invasive examination such as biopsy or even surgery.

Advanced Ultrasound Techniques for Differentiation of Benign Versus Malignant Thyroid Nodules: A Review

ABSTRACT

Grayscale ultrasound (US) is decisive in stratifying which thyroid nodules benefit from fine-needle aspiration to evaluate for malignancy. Unfortunately, a significant percentage of nodules remain indeterminate.Herein, we review the clinical considerations and diagnostic accuracy of advanced US, Doppler US, contrast-enhanced US, and US elastography techniques in the evaluation of indeterminate nodules.We conclude that these techniques may be used in combination with grayscale US to improve the assessment of lesion vascularity and tissue property.

Performance of Contrast-Enhanced Ultrasound in Thyroid Nodules: Review of Current State and Future Perspectives

Ultrasound has been established as a baseline imaging technique for thyroid nodules. The main advantage of adding CEUS is the ability to assess the sequence and intensity of vascular perfusion and hemodynamics in the thyroid nodule, thus providing real-time characterization of nodule features, considered a valuable new approach in the determination of benign vs. malignant nodules. Original studies, reviews and six meta-analyses were included in this article. A total of 624 studies were retrieved, and 107 were included in the study. As recognized for thyroid nodule malignancy risk stratification by US, for acceptable accuracy in malignancy a combination of several CEUS parameters should be applied: hypo-enhancement, heterogeneous, peripheral irregular enhancement in combination with internal enhancement patterns, and slow wash-in and wash-out curve lower than in normal thyroid tissue. In contrast, homogeneous, intense enhancement with smooth rim enhancement and "fast-in and slow-out" are indicative of the benignity of the thyroid nodule. Even though overlapping features require standardization, with further research, CEUS may achieve reliable performance in detecting or excluding thyroid cancer. It can also play an operative role in guiding ablation procedures of benign and malignant thyroid nodules and metastatic lymph nodes, and providing accurate follow-up imaging to assess treatment efficacy.

High-performance sonographical multimodal imaging of non cystic thyroid lesions: Chances of the preoperative diagnostics in relation to histopathology

AIM:

To improve preoperative diagnostics of solid non-cystic thyroid lesions by using new high-performance ultrasound techniques: optimized B-mode morphology, elastography, Color-Coded Doppler-Sonography (CCDS) and contrast enhanced ultrasound (CEUS)

MATERIALS AND METHODS:

In 33 cases solid, non-cystic thyroid lesions were rated as TIRADS 3 and up from conventional B-mode examinations. Additional high resolution Power Doppler including HR- and Glazing-Flow as optimized macrovascularization techniques, shear wave elastography and CEUS were performed on these patients by one experienced examiner. For CEUS a bolus of 1–2.4 ml Sulfurhexafluorid microbubbles (SonoVue®, Bracco, Milan, Italy) was injected into a cubital vein and then the distribution kinetics of the contrast agent were documented from the early arterial phase (10 to 15 seconds after injection) to the late venous phase (5 minutes after injection). Postoperative histopathology was the diagnostic gold standard as it provides the most reliable proof.

RESULTS:

33 patients (13 males, 20 females; age 29 –77 years; mean 55 years; SD 13 years) were included in this study. 28 of them had benign regressive thyroid nodules, 3 had adenomas and 4 were diagnosed with carcinomas (3 were histologically identified as papillary thyroid carcinomas, one as a medullary thyroid carcinoma). The volume of the thyroid gland ranged from 6.6 to 401.3 cm² (mean 72.6±92.0 cm²).

The adenoma diameters ranged from 9 to 40 mm (mean 22±16 mm) and the carcinoma diameters ranged from 19 to 33 mm (mean 26±6 mm). The 3 adenomas had different echogenicities: One was completely echofree, one was hypoechoic and one isoechoic. The 4 carcinomas however were equally characterized as hypoechoic and echofree. Two of three adenomas and all of the carcinomas showed an incomplete or diffuse margin. Micro-calcifications were found in one adenoma and in every carcinoma. However, no micro-calcifications were observed in cases of benign regressive nodules.

Performing shear-wave elastography the adenomas showed lower values than the carcinomas: The tissue velocity of the adenomas ranged from 2.86 m/s to 3.85 m/s (mean 3.32±0.5 m/s) and in carcinomas from 3.89 m/s to 5.66 m/s (mean 4.18±0.3 m/s).

Marginal hypervascularization was detected in two adenomas after applying CCDS. One adenoma was hypovascularized. The four carcinomas showed an irregular extreme hypervascularization along their margins as well as an irregular central normo- or hypervascularization in CCDS. The additional HR-Flow helped reducing artefacts.

In CEUS the dynamic capillary microvascularization of all carcinomas was very irregular with early enhancement and followed by partial or complete wash-out. In CEUS two adenomas had no wash-out and the other one showed a partial wash-out.

CONCLUSION:

Using modern multimodal imaging offers new possibilities for the differentiation between benign and malignant thyroid lesions. It is a very important diagnostic tool in addition to the B-Mode TIRADS classification and eases the decision between TIRADS 3, 4 and 5. However, additional multicenter studies are required for more detailed evaluations.

Contrast-Enhanced Ultrasound in the Differential Diagnosis of Primary Thyroid Lymphoma and Nodular Hashimoto's Thyroiditis in a Background of Heterogeneous Parenchyma

Objective

To investigate the diagnostic performance of contrast-enhanced ultrasound (CEUS) in the differentiation of primary thyroid lymphoma (PTL) and nodular Hashimoto’s thyroiditis (NHT) in patients with background of heterogeneous diffuse Hashimoto’s thyroiditis (HT).

Methods

Sixty HT patients with 64 thyroid nodules (31 PTL and 33 NHT) who had undergone CEUS examination were included in this study. With histopathological results as the reference, we evaluated the imaging features of each nodule on both conventional ultrasonography (US) and CEUS. Quantitative CEUS parameters including peak intensity (PI), time to peak (TTP), and area under the time–intensity curve (AUC) were gathered in the nodule and background parenchyma. The ratio indexes of theses parameters were calculated by the ratio of the lesion and the corresponding thyroid parenchyma. Logistic regression and receiver operating characteristic (ROC) curves analyses of valuable US indicators were further preformed to evaluate the diagnostic capability of CEUS in discrimination of PTL and NHT.

Results

Among all the observed US imaging features and CEUS parameters, 10 indicators showed significant differences between PTL and NHT (all P < 0.05). All the significant indicators were ranked according to the odds ratios (ORs). Eight of them were CEUS associated including imaging features of enhancement pattern, degree, homogeneity, and quantification parameters of PI, AUC, ratios of PI, AUC, and TTP, while indicators on conventional US, including vascularity and size ranked the last two with ORs less than 3. The five single CEUS parameters showed good diagnostic performance in diagnosis of PTL with areas under ROC curves of 0.72–0.83 and accuracies of 70.3–75.0%. The combination of CEUS imaging features and the ratios of PI, AUC, and TTP demonstrated excellent diagnostic efficiency and achieved area under ROC curve of 0.92, which was significantly higher than any of the five single parameters (all P < 0.05), with a sensitivity of 83.9%, specificity of 87.9%, and accuracy of 85.9%.

Conclusions

CEUS is an efficient diagnostic tool in the differential diagnosis of PTL and NHT for patients with diffuse HT. Conjoint analysis of CEUS imaging features and quantification parameters could improve the diagnostic values.

"Double-Flash": An Innovative Method to Diagnose Papillary Thyroid Microcarcinomas

The aim of the study was to investigate the diagnostic ability of an innovative method called "Double-Flash" during contrast-enhanced ultrasound (CEUS) examination in papillary thyroid microcarcinomas. A total of 43 nodules measuring <10 mm and with definite pathology confirmed by surgery or fine-needle aspiration biopsy (FNAB) were included in this study. The bottom of "Flash" was pressed in the 40th and 60th seconds, respectively, defined as "Double-Flash." The curve of reperfusion was evaluated and the diagnostic value of "Double-Flash" was compared with that of CEUS. Pathologic results obtained by surgery or FNAB revealed there were 27 malignant and 16 benign nodules. The sensitivity, specificity and accuracy of CEUS were 70.0%, 53.8% and 65.1%. With "Double-Flash," the sensitivity, specificity and accuracy were 92.3%, 82.3% and 88.4%, respectively. The difference was statistically significant. Higher diagnostic ability is obtained with "Double-Flash." The parameter based on the new method could improve the diagnostic performance of quantitative diagnosis in CEUS. The change in the perfusion curve after "Flash" may be a strong indicator of malignancy.

Clinical applications of Doppler ultrasonography for thyroid disease: consensus statement by the Korean Society of Thyroid Radiology

Doppler ultrasonography (US) is widely used for the differential diagnosis of thyroid nodules, metastatic cervical lymph nodes in patients with thyroid cancer, and diffuse parenchymal disease, as well as for guidance in various US-guided procedures, including biopsy and ablation. However, controversies remain regarding the appropriate use and interpretation of Doppler US. Therefore, the Korean Society of Thyroid Radiology organized a taskforce to develop a consensus statement on the clinical use of Doppler US for thyroid disease. The review and recommendations in this article are based on a comprehensive analysis of the current literature and the consensus of experts.

Contrast-enhanced ultrasound for the differential diagnosis of thyroid nodules: An updated meta-analysis with comprehensive heterogeneity analysis

The diagnostic accuracy of contrast-enhanced ultrasound (CEUS) for distinguishing malignant thyroid nodules from benign thyroid nodules remains controversial. This meta-analysis was performed to evaluate the overall diagnostic value of CEUS for the characterization of thyroid nodules. Relevant studies were identified by searching PubMed, Embase and the Cochrane Library until August 1th 2019 to assess the overall diagnostic accuracy of CEUS. 37 eligible studies were included in the present meta-analysis. The pooled sensitivity, specificity, positive likelihood rate, negative likelihood rate and diagnostic odds ratio of CEUS were 0.87, 0.83, 5.38, 0.17 and 38.94, respectively, with the AUC of 0.9263. Subgroup analysis showed the heterogeneity was greatly reduced in small nodules group (≤ 1 cm) (I2 = 0.0%), while heterogeneity was still observed in the group of variable sizes group (I2 = 69.5%). However, meta-regression analysis revealed that only diagnostic criterion was the major source of heterogeneity (p = 0.0259). The risk of publication bias was negligible (p = 0.35). CEUS exhibited high accuracy for the identification of thyroid nodules and might provide additional perfusion information for the current US imaging reporting systems.

Qualitative analysis of contrast-enhanced ultrasound in the diagnosis of small, TR3-5 benign and malignant thyroid nodules measuring ≤1 cm

OBJECTIVE

To evaluate the performance of contrast-enhanced ultrasound in the diagnosis of small, solid, TR3-5 benign and malignant thyroid nodules (≤1 cm).

METHODS

From January 2016 to March 2018, 185 thyroid nodules from 154 patients who underwent contrast enhanced ultrasound (CEUS) and fine-needle aspiration or thyroidectomy in Shanghai General Hospital were included. The χ² test was used to compare the CEUS characteristics of benign and malignant thyroid nodules, and the CEUS features of malignant nodules assigned scores. The total score of the CEUS features and the scores of the above nodules were evaluated according to the latest 2017 version of the Thyroid Imaging Reporting and Data System (TI-RADS). The diagnostic performance of the two were compared based on the receiver operating characteristic curves generated for benign and malignant thyroid nodules.

RESULTS

The degree, enhancement patterns, boundary, shape, and homogeneity of enhancement in thyroid small solid nodules were significantly different (p＜0.05). No significant differences were seen between benign and malignant thyroid nodules regarding completeness of enhancement and size of enhanced lesions (p＞0.05). The sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of the TI-RADS classification TR5 in diagnosis of malignant nodules were 90.10%, 55.95%, 74.59%, 72.22%, and 82.46%, respectively (area under the curve [AUC]=0.738; 95% confidence interval[CI], 0.663-0.813). The sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of the total score of CEUS qualitative analysis indicators were 86.13%, 89.29%, 87.57%, 90.63%, and 84.27% respectively (AUC = 0.916; 95% CI, 0.871-0.961).

CONCLUSION

CEUS qualitative analysis is superior to TI-RADS in evaluating the diagnostic performance of small, solid thyroid nodules. Qualitative analysis of CEUS has a significantly higher specificity for diagnosis of malignant thyroid nodules than TI-RADS.

ADVANCES IN KNOWLEDGE

The 2017 version of TI-RADS has recently suggested the malignant stratification of thyroid nodules by ultrasound. In this paper we applied this system and CEUS to evaluate 185 nodules and compare the results with pathological findings to access the diagnostic performance.

The features of contrast enhanced ultrasound and BRAF V600E in papillary thyroid carcinoma

Background

BRAF V600E mutation was proved to be associated with thyroid cancer. Papillary thyroid carcinoma (PTC) with positive BRAF mutation might have a more aggressive behavior. We investigated the correlation of the contrast-enhanced ultrasound (CEUS) features with BRAF 600VE in PTC.

Methods

The medical records of 1,199 patients with 1,315 nodules who underwent CEUS prior to fine needle aspiration (FNA) from January 2016 to March 2018 were retrospectively reviewed. The features of their enhancement were assessed from eight aspects: degree of enhancement, method of enhancement, homogeneity of enhancement, completeness of enhancement, boundary of the enhanced lesions, shape of the enhanced lesions, size of the enhanced lesions, and wash out period of the enhanced lesions. The patients then examined for the BRAF V600E mutation using specimens obtained from FNA.

Results

BRAF mutations were found in 888 of 1,315 nodules. The CEUS features were significantly different between BRAF-positive and BRAF-negative nodules. The BRAF mutation positive nodules were more often with larger size, hypo-enhancement, centripetal enhancement, inhomogeneous enhancement, complete enhancement, blurred boundary, irregular shape, and with wash out period at preoperative CEUS than those without BRAF mutations (P<0.001). However, no significant correlation was showed in Spearman's rank correlation between the CEUS features and BRAF mutation, except for degree of enhancement, method pattern of enhancement, and completeness of complete enhancement. Multivariate analysis showed that centripetal (OR: 1.465, 95% CI: 1.129-1.903) and no significant enhancement (OR: 0.790, 95% CI: 0.639-0.977) were predictive for the presence of BRAF mutations. The sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of no significant enhancement and centripetal enhancement of CEUS for predicting BRAF mutation were 68.3%, 40.0%, 91.6%, 11.7%, and 72.4%, 35.1%, 37.8%, 70.0%, respectively.

Conclusions

Our study indicated that preoperative thyroid nodule characteristics on CEUS might serve as a useful tool to BRAF mutation in PTC.

Predicting cervical lymph node metastasis in patients with papillary thyroid cancer (PTC) - Why contrast-enhanced ultrasound (CEUS) was performed before thyroidectomy

The objective of this research was to investigate the clinical value of contrast-enhanced ultrasound (CEUS) for prediction of cervical lymph node metastasis (CLNM) in papillary thyroid cancer (PTC).One hundred and eighty-six patients with PTC confirmed by fine needle aspiration (FNA) were preoperatively performed CEUS.A multivariate analysis was performed to predict CLNM by 15 independent variables. Receiver operating characteristic (ROC) curve analysis was used to evaluate the diagnostic performance.There were totally 37 patients with CLNM confirmed by pathology. Multivariate analysis demonstrated that intensity at peak time, capsule contact and size on CEUS were the three strongest independent predictors for CLNM. ROC analyses of these characteristics showed the areas under the curve (Az), sensitivity, and specificity were 0.650, 48.6 %, 79.8 %; 0.586, 67.6%, 49.7%; and 0.612, 56.8%, 64.4% for intensity at peak time, capsule contact, and size, respectively.The CEUS patterns of PTC are relative to not only the size of PTC but also the possibility of CLNM after thyroidectomy. CEUS seem to be a tool to predict CLNM in PTC patients.

Clinical Study of the Prediction of Malignancy in Thyroid Nodules: Modified Score versus 2017 American College of Radiology's Thyroid Imaging Reporting and Data System Ultrasound Lexicon

The clinical importance of thyroid nodules rests with the need to exclude thyroid cancer. In the present study, we developed a modified Thyroid Imaging Reporting and Data System (TI-RADS) score using gray-scale ultrasound, contrast-enhanced ultrasound (CEUS) and shear-wave elastography (SWE) images to predict malignancy of thyroid nodules and compared this modified score system with the subjective scoring criteria based on the Thyroid Imaging Reporting and Data System (TI-RADS, 2017 edition). The results revealed that by using SWE and CEUS (enhanced pattern) to downgrade TI-RADS category 4 and 5 nodules, the malignancy rate for TI-RADS category 4 and 5 nodules increased from 47.6% with American College of Radiology (ACR) TI-RADS assessment alone to 49.4% with ACR TI-RADS combined with shear wave elastography (SWE) and CEUS (enhanced pattern). Likewise, by using the modified TI-RADS to adjust TI-RADS category 3 nodules, the malignancy rate for TI-RADS category 3 nodules increased from 13.9%-20.0%. The discriminating power for detection of malignancy of the variable score 2 (ACR TI-RADS + SWE + CEUS), with an area under the curve (AUC) of 0.899 (95% confidence interval [CI]: 86.1%-93.6%), was higher than that of score 1 (ACR TI-RADS), with an AUC of 0.862 (95% CI: 81.9%-90.6%; p > 0.05). With a point 4.5 as the optimal cutoff value, a score of 1 predicted malignancy with an accuracy of 75.6%, sensitivity of 85.0% and specificity of 71.6%. However, with a point 5.5 as the optimal cutoff value, a score of 2 predicted malignancy with an accuracy of 84.9%, sensitivity of 81.0% and specificity of 86.6%. The modified TI-RADS based on ACR TI-RADS + SWE + CEUS (enhanced pattern) could contribute to a reduction in the number of biopsies performed on benign nodules and the implementation of consistent follow-up in clinical practice.

Value of differential diagnosis of contrast-enhanced ultrasound in benign and malignant thyroid nodules with microcalcification

Value of differential diagnosis of contrast-enhanced ultrasound in benign and malignant thyroid nodules with microcalcification was explored. A total of 184 patients with thyroid nodules with microcalcification, treated in People's Hospital of Shanxi Province from April 2015 to March 2017, were selected as research subjects. Contrast-enhanced ultrasound was used for imaging examination of the thyroid nodules. Three regions of interest were drawn at the positions with the strongest ultrasound imaging, for which the time-intensity curve (TIC), time to peak (Tp), peak intensity (Peak), area under curve (AUC) and mean transit time (MTT) were obtained separately. The features of contrast-enhanced ultrasound for malignant thyroid nodules were manifested as irregular focus edge, unclear boundary, low fiber reinforcement of the whole focus, uneven distribution of images and blood perfusion defect inside the focus, especially severe blood perfusion defect in the nodule center. The TIC showed a slow ascending and slow descending trend in general. The TIC features and the features of contrast-enhanced ultrasound for malignant thyroid nodules were prominently different from those for benign thyroid nodules. Compared with those in the surrounding normal tissues of thyroid gland, the Peak was remarkably shorter, and the AUC was notably smaller in the center and edge of malignant thyroid nodules (P<0.05); and the nodule center had obviously shorter Peak and smaller AUC than the nodule edge (P<0.05). Furthermore, in comparison with those of malignant thyroid nodules, the Peak was extended and AUC was enlarged markedly in the center and edge of benign thyroid nodules (P<0.05). In conclusion, the contrast-enhanced ultrasound can preferably compare the lesions of benign and malignant thyroid nodules with microcalcification, which possesses certain value in the differential diagnosis of benign and malignant thyroid nodules.

Sonographic Characteristics of Papillary Thyroid Carcinoma with Coexistent Hashimoto's Thyroiditis: Conventional Ultrasound, Acoustic Radiation Force Impulse Imaging and Contrast-Enhanced Ultrasound

Our objective was to provide the various sonographic characteristics of papillary thyroid carcinomas for Hashimoto's thyroiditis (HT) patients, including conventional ultrasound (US), acoustic radiation force impulse Virtual Touch imaging and quantification (ARFI-VTIQ) and contrast-enhanced ultrasound (CEUS). Sixty-nine HT patients with 85 thyroid nodules (TNs) (49 malignant and 36 benign) were enrolled in this study. We evaluated the size, shape, margin, echogenicity, presence of halo, calcification, vascularity and ARFI-VTIQ and CEUS parameters for each nodule and compared the findings with the reference standards of histopathological and/or cytologic results. Univariate analysis indicated that compared with benign TNs with HT, papillary thyroid carcinomas with HT more often had taller-than-wider shapes, ill-defined margins, microcalcifications, peripheral vascularity, relatively harder stiffness with a higher shear wave speed, hypo-enhancement, peak intensity index <1 and area under the curve index <1 at pre-operative US, ARFI-VTIQ and CEUS. Multivariate analysis revealed that ill-defined margins, microcalcifications and peak intensity index <1 are independent characteristics related to malignant TNs for their differentiation from benign TNs (all p < 0.05). Our study indicated that pre-operative multiparameter US characteristics may serve as a useful tool to identify malignant TNs in HT patients.

The diagnostic accuracy of contrast-enhanced ultrasound for the differentiation of benign and malignant thyroid nodules: A PRISMA compliant meta-analysis

BACKGROUND

Contrast-enhanced ultrasound (CEUS) is a non-invasive method that has been used in the diagnosis of several diseases. Recently, CEUS has been used in the differentiation of benign and malignant thyroid nodules. However, the performance of CEUS in thyroid nodules has not been studied clearly.

METHODS

The databases of Pubmed, Embase, Cochrane library and the unpublished studies were systematically searched for candidate inclusions, with the use of CEUS in differentiating the benign and malignant thyroid nodules. The quality of included studies was assessed using Quality Assessment of Diagnostic Accuracy Studies (QUADAS) questionnaire. The pooled estimates of sensitivity, specificity, diagnostic odds ratio (DOR), positive and negative likelihood ratio (NLR) were calculated using STATA software version 14.0.

RESULTS

Totally 33 diagnostic studies were included for further analysis. The quality of included studies was relatively high using QUADAS method. The pooled estimates of sensitivity and specificity were 0.88 (95% CI 0.85, 0.91) and 0.88 (95% CI 0.83, 0.91), respectively. In addition, the DOR, the positive and NLRs were pooled positive LR and the negative LR were 54 (95% CI 33, 89), 7.1% (5.2%, 9.8%), and 0.13% (0.10%, 0.18%). No significant publication bias was observed.

CONCLUSIONS

Our meta-analysis further indicated that CEUS is a useful tool in differentiating benign and malignant thyroid nodules, with high sensitivity and specificity.

Value of Contrast-Enhanced Ultrasound and Acoustic Radiation Force Impulse Imaging for the Differential Diagnosis of Benign and Malignant Thyroid Nodules

Objectives: To assess the value of contrast-enhanced ultrasound (CEUS) and acoustic radiation force impulse (ARFI) imaging for the differential diagnosis of benign and malignant thyroid nodules.

Methods: CEUS was performed in eighty-eight thyroid nodules. The patterns of CEUS were analyzed, and ARFI was then performed. The shear wave velocities (SWVs) of the nodules and the surrounding normal thyroid tissue were obtained. The areas under the curve (AUCs) and cut-off value were obtained by a receiver operating characteristic (ROC) curve analysis. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and diagnostic rate of each modality were assessed and compared using pathological diagnosis.

Results: Among 88 nodules, 29 nodules were malignant and 59 were benign. The sensitivity, specificity, PPV, NPV, and diagnostic rate of CEUS were 79.3, 91.5, 82.1, 90, and 87.5%, respectively. Using a cut-off value of 2.565 m/s for SWV, the sensitivity, specificity, PPV, NPV and diagnostic rate for malignancy were 75.9, 94.9, 88.0, 88.9, and 88.6%, respectively. The AUC was 0.878. The sensitivity, specificity, PPV, NPV and diagnostic rate of CEUS in combination with ARFI were 93.1, 89.8, 81.8, 96.3, and 90.9%, respectively.

Conclusion: Both CEUS and ARFI are valuable for the differential diagnosis of benign and malignant thyroid nodules. Combining these two methods can improve the diagnostic rate.

Significance of contrast-enhanced ultrasonography in differential diagnosis of thyroid nodules

The present study was aimed to compare the application values between 2-dimensional color Doppler ultrasonography (2DUS) and contrast-enhanced ultrasonography (CEUS) in the differential diagnosis of thyroid malignant nodules.A total of 124 patients suspectedly diagnosed with malignant thyroid nodules under conventional gray-scale ultrasonography were recruited in this study. All enrolled patients were examined by both 2DUS and CEUS.A total of 153 nodules (94.44%) and 45 cases (90.00%) with malignant nodules were detected by the CEUS. No significant differences were noted in nodule detection rates between 2DUS and CEUS (χ = 1.170, P = .279; χ = 0.796, P = .372). The aspect ratio, microcalcification, internal echo, borderline, Vmax, resistance index, and total scores of malignant nodules were higher than those of benign nodules (all P < .05) when diagnosed by 2DUS. The peripheral/internal enhancement time, peak intensity, local enhancement, ring enhancement, and total scores of malignant nodules were significantly higher compared with those of benign nodules (all P < .05) by CEUS. Total score of malignant nodules diagnosed by 2DUS was approximately 3.5 and 2.3 points for CEUS. The diagnostic accuracy of 2DUS as observed by area under the curve was 0.821 with the cut-off value of 3.9, the sensitivity was 82.5%, and the specificity was 85.6%. The diagnostic accuracy of CEUS was 0.862 with the cut-off value of 2.8, the sensitivity was 86.7%, and the specificity was 91.3%.Both 2DUS and CEUS are worthy of application values in the differential diagnosis from benign to malignant thyroid nodules.

Application of contrast-enhanced ultrasound for evaluation of thyroid nodules

Contrast-enhanced ultrasound (CEUS) is widely used to evaluate tumor microcirculation, which is useful in the differential diagnosis between benignity and malignancy. In the last 10 years, the applicability of CEUS to thyroid nodules has greatly improved due to technological refinements and the development of second-generation contrast agents. In this review, we summarize the applications of CEUS for thyroid nodules, focusing on the imaging findings of malignant and benign nodules in the existing literature and the use of those findings to predict malignancies, with an additional brief description of the utilization of CEUS for other thyroid-related diseases.

Revised Value of Contrast-Enhanced Ultrasound for Solid Hypo-Echoic Thyroid Nodules Graded with the Thyroid Imaging Reporting and Data System

The use of ultrasound in differentiation of benign and malignant solid hypo-echoic thyroid nodules is a dilemma in clinical practice. The aim of this study was to investigate the revised value of contrast-enhanced ultrasound (CEUS) for differentiating solid hypo-echoic thyroid nodules using the Thyroid Imaging Reporting and Data System (TI-RADS).The study included 135 patients with 135 nodules confirmed by fine-needle aspiration and/or surgery. Every nodule underwent both conventional US and CEUS. Binary logistic regression analysis for conventional US features revealed that irregular shape, microcalcification and height greater than width were significant malignant predictive features. Binary logistic analysis for CEUS features indicated that hetero-enhancement, slow wash-in, an ill-defined enhancement border and fast wash-out were significantly associated with malignancy. The areas under the curve of the TI-RADS, CEUS and the combination were 0.806, 0.934 and 0.950, respectively. CEUS is a potentially useful tool in the differentiation of solid hypo-echoic thyroid nodules.

Diagnostic Efficiency of Quantitative Contrast-Enhanced Ultrasound Indicators for Discriminating Benign From Malignant Solid Thyroid Nodules

OBJECTIVES

We aimed to determine the most efficient quantitative parameters to establish a contrast-enhanced ultrasound (US) assessment system for distinguishing between benign and malignant thyroid nodules.

METHODS

A total of 167 patients with thyroid solitary nodules had the diagnosis confirmed by surgery or fine-needle aspiration. Quantitative contrast-enhanced US indicators (time to peak, time from peak to one-half, ascend slope, descend slope, peak intensity, and area under the curve [AUC]) were gathered in nodule and perinodule areas. Univariate and multivariate logistic regression analyses were performed. Receiver operating characteristic curves were generated. Sensitivities, specificities, and positive and negative predictive values were calculated to identify the best cutoff value.

RESULTS

The univariate logistic regression model showed that the peak intensity, ascend slope, descend slope, and AUC were significant indicators for discriminating benign from malignant nodules under contrast-enhanced US (P < .0001). For thyroid nodules, low peak intensity, ascend slope, and AUC and high descend slope values were significant indicators of malignancy. However, in perinodule areas, high peak intensity, ascend slope, and AUC and low descend slope values were significantly associated with malignancies. The cutoff values for the nodule peak intensity, ascend slope, descend slope, and AUC were 20.75, 0.91, -0.2, and 1818.23, respectively. The cutoff values for the ratios of the nodule versus perinodule peak intensity, ascend slope, descend slope, and AUC were 0.90, 0.95, 0.96, and 0.96. The nodule-to-perinodule peak intensity ratio showed the best diagnostic efficiency, with 80.41% sensitivity and 80.00% specificity.

CONCLUSIONS

Quantitative contrast-enhanced US indicators help discriminate benign from malignant thyroid nodules. The nodule-to-perinodule peak intensity ratio showed the best diagnostic efficiency.

An evaluation of the clinical diagnostic value of contrast-enhanced ultrasound combined with contrast-enhanced computed tomography in space-occupying lesions of the kidney

BACKGROUND

There are a variety of space-occupying lesions of the kidney, and the benign lesions may be difficult to differentiate from the malignant ones. Therefore, an accurate judgment of the benign and malignant nature of the space-occupying lesions of the kidney is of high importance for the treatment and prognosis of these patients.

OBJECTIVE

To evaluate the diagnostic value of contrast-enhanced ultrasound (CEUS) combined with contrast-enhanced computed tomography (CECT) in space-occupying lesions of the kidney.

DATA AND METHODS

Three hundred and sixty-seven patients with space-occupying lesions of the kidney (378 lesions) were examined by CEUS and CECT, respectively, then, a combined diagnosis was made after the combination of CEUS and CECT by a multidisciplinary team. The diagnoses from the three methods were compared. The pathological results were taken as the gold standard. The sensitivity, specificity, positive and negative predictive values and area under the receiver operating characteristic (ROC) curve were calculated for the three methods. Thus, the diagnostic value of the three methods was assessed.

RESULTS

Of the 378 lesions examined, there were 301 malignant lesions and 77 benign lesions. The combined examination revealed 303 malignant lesions, with 9 benign lesions mistakenly diagnosed as malignant ones; thus, the misdiagnosis rate was 11.7%. By using the combined examination, 75 benign lesions were diagnosed, with the missed diagnosis of 7 malignant lesions, so the missed diagnosis rate was 2.3%. The sensitivity, specificity, positive and negative predictive values and area under the ROC curve with the combined examination of CEUS and CECT were 97.67% (0.950-0.989), 88.31% (0.785-0.942), 97.03% (0.942-0.985), 90.67% (0.811-0.958) and 0.930 (0.887-0.973), respectively. As compared with either CEUS or CECT alone, the difference in these indicators was of statistical significance (P<0.05). The combined examination greatly improved the sensitivity, specificity and accuracy of the diagnosis of the space-occupying lesions of the kidney.

CONCLUSION

CEUS and CECT each have advantages and disadvantages in the diagnosis of the space-occupying lesions of the kidney. The two techniques can be used in combination to compensate for the respective defects. More salient benefits can be reaped from the combined examination than from either technique used alone.

Shear wave elastography and contrast-enhanced ultrasonography in the diagnosis of thyroid malignant nodules

The aim of the present study was to evaluate the value of shear wave elastography (SWE) and contrast-enhanced ultrasonography (CEUS) in the diagnosis of thyroid malignant nodules. A total of 253 patients with 319 thyroid nodules were subjected to two-dimensional ultrasound (2DUS) and CEUS examinations prior to thyroidectomy between March, 2014 and December, 2015. Young's modulus value for each nodule on 2DUS and CEUS images were recorded. The sensitivity, specificity and accuracy of 2DUS, SWE and CEUS in the diagnosis of thyroid malignant nodules were assessed. The results demonstrated that, of the 319 nodules that were pathologically confirmed, 183 were malignant and 136 were benign. The area under the receiver operating characteristic curve as a result of SWE diagnosis was 0.77. When the threshold of the Young's modulus value was ≥27.65 kPa in the diagnosis of malignant thyroid nodules, SWE exhibited a sensitivity of 84.55% (115/136), a specificity of 84.15% (154/183) and an accuracy of 84.32% (269/319). US contrast imaging of malignant thyroid nodules revealed a major tendency for early hypoenhancement and hypoenhancement. CEUS exhibited a sensitivity of 87.5% (119/136), a specificity of 86.33% (158/183) and an accuracy of 86.83% (277/319) in the diagnosis of malignant thyroid nodules. Compared with 2DUS, SWE, CEUS and their combined use exhibited statistically significant differences in the diagnosis of thyroid malignant nodules in terms of sensitivity, specificity and accuracy (χ²=9.220,15.310 and 40.296, respectively; P=0.000); SWE or CEUS did not differ significantly in the diagnosis of thyroid malignant nodules in terms of sensitivity, specificity or accuracy (χ²=0.737;P=0.542); Compared with the use of SWE or CEUS alone, their combination exhibited statistically significant differences in the diagnosis of malignant thyroid nodules in terms of sensitivity, specificity and accuracy (χ²=12.264 and 6.939, respectively; P=0.000,0.005). In conclusion, the high accuracy of the combined use of SWE and CEUS in the diagnosis of malignant thyroid nodules is of great clinical value.

Usefulness of combined use of contrast-enhanced ultrasound and TI-RADS classification for the differentiation of benign from malignant lesions of thyroid nodules

Purpose

To study the thyroid image reporting and data system (TI-RADS) classification and the contrast-enhanced ultrasound (CEUS) enhancement pattern of thyroid nodules, and to determine whether combined use of both methods is helpful in the diagnosis of thyroid nodules.

Methods

A total of 319 thyroid nodules in 246 patients were assessed with TI-RADS, CEUS and a combination of both methods. The diagnostic performance of TI-RADS, CEUS and a combination of both methods was compared.

Results

The accuracy in the diagnosis of thyroid nodules was 90.3 % for TI-RADS, 90.0 % for CEUS and 96.0 % for a combination of both methods respectively. A statistically significant difference was not observed in the diagnostic accuracy of CEUS and TI-RADS (P > 0.05). However, a significant difference was observed between a combination of both methods and either alone (P < 0.01). A combination of both methods showed high sensitivity, specificity and accuracy for TI-RADS classifications of 4a and 4b thyroid nodules compared with TI-RADS alone (P < 0.01) and a statistically significant difference was not observed for thyroid nodules classified as 2, 3, and 5 (P > 0.05).

Conclusions

The improved TI-RADS, when combined with CEUS, could significantly improve the diagnostic accuracy for thyroid nodules, especially for TI-RADS class-4 thyroid nodules.

Key Points

• TI-RADS can be used as the primary diagnostic standard for thyroid nodules

• CEUS can be used as an important complement to TI-RADS

• The improved TI-RADS can significantly improve the qualitative diagnostic accuracy

Diagnostic value of contrast-enhanced ultrasound in solid thyroid nodules with and without enhancement

We aimed to investigate different enhancement patterns of solid thyroid nodules on contrast-enhanced ultrasound (CEUS) and then to evaluate the corresponding diagnostic performance in the differentiation of benign and malignant nodules with and without enhancement. 229 solid thyroid nodules in 196 patients who had undergone both conventional ultrasound and CEUS examinations were classified into enhancement and non-enhancement groups. Besides, different enhancement patterns in the enhancement group were characterised with five indicators including arrival time, mode of entrance, echo intensity, homogeneity, and washout time. Then aforementioned indicators were compared between benign and malignant nodules of different sizes (<10 mm and >10 mm), and diagnostic performance of significant enhancement indicators was calculated. As for the enhancement group, there were statistically significant differences of <10 mm subgroup among three CEUS indicators including arrival time, mode of entrance, and washout time between malignant and benign thyroid nodules (p < 0.05), while all CEUS indicators showed statistically significant differences in the total group and ≥10 mm subgroup (p < 0.05). All the five CEUS indicators displayed better diagnostic performance with specificity (92.86, 92.14, 95.71, 90.71, and 90.71 %, respectively) and diagnostic accuracy (80.79, 79.48, 74.67, 75.11, and 81.66 %, respectively), while the sensitivity and negative predictive value of non-enhancement were 95.51 and 95.83 %, respectively, with an accuracy of 77.29 %. CEUS is a very promising diagnostic technique that could improve the diagnostic accuracy of identifying benign thyroid lesions to spare a large number of patients an unnecessary invasive procedure.

Contrast-enhanced ultrasound and real-time elastography in the differential diagnosis of malignant and benign thyroid nodules

The diagnostic value of contrast-enhanced ultrasound (CEUS) or real-time elastography (RTE) alone, as well as a combination of CEUS and RTE, in distinguishing benign from malignant thyroid nodules was investigated. Between August 2012 and June 2014, a total of 97 consecutive patients (50 male and 47 female patients; mean age, 48.6±12.4; age range, 27-70 years) with thyroid nodules referred for surgical treatment were examined by CEUS and RTE. The final diagnosis was obtained based on histological findings. Image analysis of the CEUS and RTE scans was performed. Considering the postoperative pathological results as the golden standard, a receiver operating characteristic (ROC) curve was constructed. Subsequently, the sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and accuracy of CEUS alone, RTE alone and CEUS + RTE combination were calculated. Pathological examination showed 66 papillary carcinomas and 43 benign lesions, including 21 adenomas and 22 nodular goiters. The sensitivity, specificity, PPV, NPV and accuracy of CEUS were 81.82, 90.70, 93.10, 90.70 and 85.32%, respectively. In the case of RTE, the sensitivity, specificity, PPV, NPV and accuracy were 80.30, 88.37, 91.38, 88.37 and 83.49%, respectively. Furthermore, the combination of CEUS + RTE had a sensitivity of 95.45%, specificity of 95.35%, PPV of 96.92%, NPV of 95.35% and accuracy of 95.41%. Therefore, the CEUS + RTE combination showed a significantly higher sensitivity and specificity compared with CEUS or RTE alone (all P<0.05). Based on ROC analysis, the area under the curve (AUC) for CEUS, RTE and CEUS + RTE combination was 0.883, 0.863 and 0.959, respectively. The AUC of RTE alone was significantly lower compared with that of the CEUS + RTE combination. In conclusion, our results demonstrate that CEUS + RTE combination significantly increases the diagnostic performance for differential diagnosis of malignant and benign thyroid nodules compared with CEUS or RTE alone.

Diagnostic value of contrast-enhanced ultrasound in papillary thyroid microcarcinoma

The aim of the present study was to explore the value and characteristics of contrast-enhanced ultrasound (CEUS) in the diagnosis of papillary thyroid microcarcinoma (PTMC). By analyzing CEUS information of 130 nodules obtained from 106 patients with PTMC, who had been diagnosed by surgery and pathological analysis, CEUS characteristics of PTMC nodules were concluded. Based on the results, the PTMC nodules were divided into three groups as follows: 32 nodules (24.62%) were found to be enhanced earlier than the surrounding normal thyroid tissue, 95 nodules (73.08%) were enhanced at the same time as the normal thyroid tissue and 3 nodules (2.30%) were enhanced later than the normal thyroid tissue. The results also demonstrated that the peak enhancement intensity of the 130 nodules was lower compared with the irregular intensity of the normal parenchyma in corresponding thyroids, and that PTMC enhancement washed out faster than in normal thyroid parenchyma. In conclusion, the PTMC characteristics that CEUS can detect may improve the diagnostic accuracy and provide valuable information for the treatment of the disease.

Logistic Regression Analysis of Contrast-Enhanced Ultrasound and Conventional Ultrasound Characteristics of Sub-centimeter Thyroid Nodules

The purpose of the study described here was to determine specific characteristics of thyroid microcarcinoma (TMC) and explore the value of contrast-enhanced ultrasound (CEUS) combined with conventional ultrasound (US) in the diagnosis of TMC. Characteristics of 63 patients with TMC and 39 with benign sub-centimeter thyroid nodules were retrospectively analyzed. Multivariate logistic regression analysis was performed to determine independent risk factors. Four variables were included in the logistic regression models: age, shape, blood flow distribution and enhancement pattern. The area under the receiver operating characteristic curve was 0.919. With 0.113 selected as the cutoff value, sensitivity, specificity, positive predictive value, negative predictive value and accuracy were 90.5%, 82.1%, 89.1%, 84.2% and 87.3%, respectively. Independent risk factors for TMC determined with the combination of CEUS and conventional US were age, shape, blood flow distribution and enhancement pattern. Age was negatively correlated with malignancy, whereas shape, blood flow distribution and enhancement pattern were positively correlated. The logistic regression model involving CEUS and conventional US was found to be effective in the diagnosis of sub-centimeter thyroid nodules.

Contrast-enhanced sonography for the identification of benign and malignant thyroid nodules: Systematic review and meta-analysis

PURPOSE

The use of contrast-enhanced sonography (CEUS) has yielded promising results in the differentiation of thyroid nodules. We conducted this meta-analysis to assess its performance in identifying and distinguishing between benign and malignant thyroid nodules.

METHODS

PubMed, Medline, Embase, and the Cochrane Library were searched for studies published through the end of December 2013. Sensitivity, specificity, positive and negative likelihood ratios, diagnostic odds ratio, and area under the curve were calculated.

RESULTS

A total of 13 studies were included in this meta-analysis. For the diagnosis of malignant thyroid nodules worldwide, the overall mean rates of sensitivity and specificity of CEUS were 90% (95% confidence interval [CI], 88-93%) and 86% (95% CI, 83-89%), respectively. The summary diagnostic odds ratio was 52.83 (95% CI, 21.71-128.55), and the area under the curve for the summary receiver operating characteristic curve was 0.94 (95% CI, 0.90-0.98).

CONCLUSIONS

This meta-analysis indicates that CEUS may be a valuable supplemental method, with high rates of sensitivity and specificity, to use for identifying and distinguishing between benign and malignant thyroid nodules.

Association between real-time contrast-enhanced ultrasound characteristics and thyroid carcinoma size

The aim of the present study was to discuss the various appearances of thyroid carcinomas on real-time contrast-enhanced ultrasound (CEUS) in association with tumor size. The appearances of 68 thyroid carcinomas confirmed by pathology were retrospectively analyzed. The lesions were divided into 3 groups by maximum diameter <10, 10-20 and >20 mm, respectively. For each lesion, absolute enhancement beginning time, relative enhancement beginning time, homogeneity, with or without perfusion defect, enhancement order, enhancement intensity and enhancement margin type were evaluated by CEUS. The majority of thyroid carcinomas were enhanced later than the surrounding thyroid gland. The predominant enhancement pattern of all the 68 thyroid carcinomas in the 3 groups was mainly heterogeneous and concentric enhancement, and the lesions mostly showed less clear or poorly defined enhancement margins. There was no significant difference among the 3 groups (P>0.05). Thyroid carcinoma with diameters <10 and 10-20 mm exhibited low enhancement, while thyroid carcinomas with diameters >20 mm showed high enhancement. With the increase of the lesion's maximum diameter, the probability of perfusion defect increased by 28.57, 54.29 and 75.00%, respectively, and there was a significant difference among the 3 groups (P<0.05). CEUS characteristics are associated with tumor size to a certain extent, and can provide valuable information for clinical diagnosis.

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.

Contrast-enhanced sonography of thyroid nodules

PURPOSE

To investigate the value of contrast-enhanced ultrasound (CEUS) in the differentiation of benign and malignant nodules.

METHODS

One hundred eighty-nine patients with 213 thyroid nodules were enrolled in this retrospective study. All patients underwent preoperative CEUS and were subsequently scheduled for surgery. The pathology results were obtained after surgery. The time-intensity curves were plotted with TomTec software. The quantitative parameters of the time-intensity curve, such as the maximum intensity of peak (IMAX), the rise time from 10% to 90% of the IMAX, and the time to peak, were compared between the benign and malignant nodules.

RESULTS

There were no significant differences in the rise time or the time to peak among thyroid papillary carcinoma, nodular goiter, and follicular adenoma. However, a significant difference was identified in the IMAX.

CONCLUSIONS

A quantitative evaluation of CEUS is helpful to differentiate benign and malignant thyroid nodules.

Conventional US, elastography, and contrast enhanced US features of papillary thyroid microcarcinoma predict central compartment lymph node metastases

Lymph node metastases at the time of diagnosis have a major impact on both therapeutic strategy and tumor recurrence for patients with papillary thyroid microcarcinoma (PTMC). Our objective was to evaluate the usefulness of PTMC characteristics on ultrasonography for predicting central compartment lymph node metastases (CCLNM) of PTMC. One hundred twenty seven patients who underwent surgery for PTMC were enrolled in this study. The relationship between the CCLNM and the characteristics on conventional US, elastographic, and contrast enhanced ultrasound (CEUS) were investigated. Univariate analysis indicated that PTMCs with CCLNM were more often nodule irregular shape, microcalcifications, hyperenhancing or isoenhancing parametric maps, and peak index ≥1 at preoperative US and CEUS than those without CCLNM (P< 0.01, 0.05, 0.01 and 0.05 respectively). Multivariate analysis showed that microcalcification (OR:2.378, 95% CI: 1.096–5.158) and hyperenhancement or isoenhancement (OR:2.8, 95% CI: 1.287–6.094) were predictive for the presence of CCLNM. Elastography score was not significantly different between the groups. Our study indicated that preoperative thyroid nodule characteristics on conventional US and CEUS may serve as a useful tool to predict central compartment lymph node metastases in PTMC.

Contrast-Enhanced Ultrasound for Differentiation of Benign and Malignant Thyroid Lesions

Objective.

Contrast-enhanced ultrasound (CEUS) is a new noninvasive modality for the diagnosis of thyroid nodules. However, the performance of CEUS in differentiating malignant and benign thyroid nodules has not been systematically evaluated. This meta-analysis was performed to assess the accuracy of CEUS in diagnosing thyroid nodules.

Data Sources

PubMed, Embase, and the references of included studies were examined.

Review Methods

We recorded the characteristics of the included studies and assessed the quality of each study using the Quality Assessment of Diagnostic Accuracy Studies tool. The pooled sensitivity, specificity, positive likelihood ratio (LR), negative LR, diagnostic odds ratio (DOR), and area under the curve (AUC) were calculated. We also evaluated the publication bias.

Results

This meta-analysis included 7 studies with a total of 597 thyroid nodules. The pooled the sensitivity, specificity, and positive and negative LR were 0.853, 0.876, 5.822, and 0.195, respectively. The DOR and AUC were 34.730 and 0.9162, respectively. Heterogeneity existed between the included studies. The results of subgroup analyses indicated that the evaluation processes are likely the predominant source of heterogeneity. No significant publication bias was observed.

Conclusion

Contrast-enhanced ultrasound is a promising noninvasive technique for the differential diagnosis of benign and malignant thyroid nodules and could be a valuable supplemental method to fine-needle aspiration.

Contrast-enhanced ultrasound (CEUS) facilitated US in detecting lateral neck lymph node metastasis of thyroid cancer patients: diagnosis value and enhancement patterns of malignant lymph nodes

OBJECTIVES

To examine the value of CEUS as a non-invasive tool in detecting lateral neck metastasis (LNM) and the enhancement patterns of malignant lymph nodes (LN) for thyroid cancer patients.

METHODS

Eighty-two consecutive patients, who underwent both preoperative non-enhanced US and CEUS examinations, were retrospectively reviewed. All patients underwent lateral neck dissection (LND). Enhancement patterns of 102 collected LNs matching to CEUS findings were analyzed.

RESULTS

CEUS detected LNM in 53 of 65 patients, showing a higher sensitivity and accuracy than that of conventional US (p = 0.109 and p = 0.154, respectively). Thirteen patients' surgical procedures were altered by CEUS findings, including nine true positive and four false positive cases. Five patients' surgical procedures were altered by conventional US findings, including two true positive and three false positive cases. Heterogeneous enhancement, perfusion defects, microcalcification, and centripetal/hybrid enhancement were all specific criteria for malignant LNs in univariate analysis. In multivariate analysis, only heterogeneous enhancement and centripetal/hybrid enhancement were significantly related to LN metastasis (p = 0.000 and p = 0.037, respectively).

CONCLUSIONS

CEUS may be a potential tool to facilitate conventional US in detecting LNM. Heterogeneous enhancement and centripetal/hybrid enhancement are useful criteria to distinguish between malignant and benign LNs.

KEY POINTS

• CEUS findings facilitated conventional US in detecting LNM. • Heterogeneous, centripetal/hybrid enhancement, microcalcification and perfusion defects were specific criteria of malignant LNs. • Heterogeneous and centripetal/hybrid enhancement were significantly related to LN metastasis in multivariate analysis.

Correlation between maximum intensity and microvessel density for differentiation of malignant from benign thyroid nodules on contrast-enhanced sonography

OBJECTIVES

The purpose of this study was to retrospectively evaluate contrast-enhanced sonography for differentiation of benign and malignant thyroid nodules by analyzing the correlation between maximum intensity and microvessel density.

METHODS

From February 2010 to May 2012, 122 patients (85 female and 37 male; mean age ± SD, 45 ± 9.1 years) with thyroid nodules (62 papillary thyroid carcinomas, 30 nodular goiters, and 30 adenomas) that underwent routine thyroid sonography and were diagnosed by surgery were included in this study. Contrast-enhanced sonography was performed, and enhancement patterns were classified into 3 groups: high, equal, and low enhancement. As a time-intensity curve parameter, the correlation of maximum intensity with CD31 and CD34 microvessel density counts was analyzed.

RESULTS

On contrast-enhanced sonography, most patients with papillary thyroid carcinomas showed a heterogeneous low enhancement pattern, whereas most patients with nodular goiters showed an equal enhancement pattern, and patients with adenomas showed a high enhancement pattern. The detection of papillary thyroid carcinomas with low enhancement had sensitivity of 96.8%, specificity of 95.0%, and accuracy of 95.9%. Compared with the papillary thyroid group, the mean microvessel density counts were significantly higher in the nodular goiter and adenoma groups (P< .05). We also found that the maximum intensity was significantly associated with CD31 and CD34 counts (CD31, r = 0.963; P < .01; CD34, r = 0.968; P < .01).

CONCLUSIONS

Maximum intensity has a significant relationship with microvessel density. Contrast-enhanced sonography is a practical and convenient means for differentiating benign from malignant thyroid nodules.