Diagnostic value of contrast-enhanced ultrasound in thyroid nodules with calcification

Ultrasound Contrast Agents: Current Role in Adults and Children for Various Indications

Intravenous contrast-enhanced ultrasound (CEUS) is a rapidly evolving imaging technique that uses a microbubble contrast agent to enhance ultrasonographic images by augmenting characterization of blood vessels and organ perfusion. CEUS is considered as a useful problem-solving tool and as an indicated first-line imaging modality in select settings. CEUS technique has an inherent advantage over its predecessor B-mode and Doppler imaging. This article reviews different approved and off-label use of CEUS in the pediatric and adult population and also discusses Food and Drug Administration-approved contrast agents in the United States, their reported side effects, and ongoing efforts in the field.

The Utility of Contrast-Enhanced Ultrasound (CEUS) in Assessing the Risk of Malignancy in Thyroid Nodules

BACKGROUND

Ultrasonography is a primary method used in the evaluation of thyroid nodules, but no single feature of this method predicts malignancy with high accuracy. Therefore, this paper aims to assess the utility of contrast-enhanced ultrasound (CEUS) in the differential diagnosis of thyroid nodules.

METHODS

The study group comprised 188 adult patients (155 women and 33 men) who preoperatively underwent CEUS of a thyroid nodule classified as Bethesda categories II-VI after fine-needle aspiration biopsy. During the CEUS examination, 1.5 mL of SonoVue contrast was injected intravenously, after which 15 qualitative CEUS enhancement patterns were analysed.

RESULTS

The histopathologic results comprised 65 benign thyroid nodules and 123 thyroid carcinomas. The dominant malignant CEUS features, such as hypo- and heterogeneous enhancement and slow wash-in phase, were evaluated, whereas high enhancement, ring enhancement, and a slow wash-out phase were assessed as predictors of benign lesions. Two significant combinations of B-mode and CEUS patterns were noted, namely, hypoechogenicity with heterogeneous enhancement and non-smooth margins with hypo- or iso-enhancement.

CONCLUSIONS

The preliminary results indicate that CEUS is a useful tool in assessing the risk of malignancy of thyroid lesions. The combination of the qualitative enhancement parameters and B-mode sonographic features significantly increases the method's usefulness.

Ultrasound microflow patterns help in distinguishing malignant from benign thyroid nodules

BACKGROUND

Vascular features are not commonly used to evaluate thyroid nodules by conventional ultrasound due to the low sensitivity. Superb Microvascular Imaging (SMI) is a new ultrasonic Doppler technology that specializes in depicting microvessels and low-speed flow. The objective of this study was to explore the value of microflow features on SMI in differentiating malignant from benign thyroid nodules.

METHODS

One hundred and seventy-seven adult patients with thyroid nodules in our center from October 2021 to June 2022 with available histopathological results were recruited, including 125 malignant nodules and 123 benign nodules. Preoperative ultrasound was performed using greyscale, Color Doppler Flow Imaging (CDFI), monochrome SMI (mSMI) and color SMI (cSMI). Vascular features such as flow richness, microflow distribution and microflow patterns of malignant thyroid nodules were compared with those of benign nodules.

RESULTS

Penetrating vessel ≥ 1 (82.4% in the malignant group vs. 30.9% in the benign group, P < 0.001), the crab claw-like pattern (64.0% vs. 10.6%, P < 0.001) and the root hair-like pattern (8.0% vs. 2.4%, P = 0.049) were common in malignant thyroid nodules, among which the crab claw-like pattern was an independent risk factor for malignant thyroid nodules. The wheel-like pattern (1.6% in the malignant group vs. 33.3% in the benign group, P < 0.001) and the arborescent pattern (0 vs. 19.5%, P < 0.001) were more likely to appear in benign nodules. The diagnostic specificities of the crab claw-like pattern and the root hair-like pattern for malignant thyroid nodules were 0.894, 0.976, and the positive predictive values were 0.860, 0.769. The diagnostic specificities of the wheel-like pattern and the arborescent pattern for benign thyroid nodules were 0.984, 1.000, and the positive predictive values were 0.953, 1.000.

CONCLUSIONS

The crab claw-like pattern and the root hair-like pattern were microflow characteristics of malignant thyroid nodules. The wheel-like pattern and the arborescent pattern could help exclude the diagnosis of thyroid cancer.

Adult-type rhabdomyoma of the thyroid: A case report

Adult-type rhabdomyoma (AR) is a benign myogenous neoplasm. It is rarely located in the thyroid. We present a case of a 61-year-old man, presenting with complaints of a mass found in his left neck for three years. Ultrasonography and computed tomography showed a mass in the left lobe of the thyroid. Subsequently, a fine-needle aspiration biopsy showed that the lesion was suspected to be an oncocytic neoplasm, and the patient underwent surgery. Finally, the lesion was confirmed to be an AR of the thyroid by postoperative pathological diagnosis. In conclusion, AR that occurs in the thyroid is remarkably rare. No case reports to date have described in detail the imaging findings of AR in the thyroid. This study demonstrates the imaging characteristics of a patient with AR of the thyroid, in order to provide more extensive insights to consider the differential diagnosis of thyroid lesions.

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.

Major Complication Following Kawasaki Disease in an Infant-The Development of Apical Infarction and Aneurysm Formation

Considerable advances have occurred in the understanding of Kawasaki disease, with a substantial drop in morbidity and mortality following the infusion of gamma globulin during the acute phase. Nevertheless, major complications may still occur. A 27-year-old male presented as an infant of 11 weeks when he was diagnosed as having Kawasaki disease. He was appropriately treated with aspirin and a gamma globulin infusion following his diagnosis 5 days after the onset of his illness. Despite that, he went on to develop coronary aneurysms. He represented a few weeks later with a history of inconsolable crying associated with pallor, suggestive of ischaemic chest pain. A repeat echocardiogram revealed infarction of the apex of the left ventricle with localised thrombus formation. There were persistent aneurysms within both coronary artery systems. A further infusion of gamma globulin was given. In view of the thrombus formation, he was started on warfarin. The thrombus gradually resolved with the development of a clearly defined left ventricular apical aneurysm. He has remained on warfarin, aiming for an international normalised ratio (INR) level of 2 to 2.5. He developed mild left ventricular dysfunction during late childhood, which improved following the commencement of an angiotensin-converting enzyme (ACE) inhibitor. Despite his ventricular aneurysm, there has been no documented evidence of ventricular tachycardia over the years. Repeated testing initially by nuclear perfusion scans and then by stress echocardiograms failed to show any inducible ischaemia apart from the apical ventricular aneurysm. A recent computed tomography (CT) coronary angiogram revealed an ectatic origin of the left main and the right coronary arteries with mild calcification involving the mid-portion of the latter and slight calcification of the former. His raised cholesterol level has responded well to a statin. Despite the persistence of the ventricular aneurysm, he continues to be managed conservatively, as he has remained well. The question arises as to what the long-term implications are of his left ventricle apical aneurysm. Should it be excised? Is he at risk for ventricular tachycardia and sudden death? In addition, although the coronary aneurysms have resolved, the CT coronary angiogram shows calcium plaques in both coronary arteries at the site of the earlier aneurysms. This finding raises the question as to whether all children who develop coronary artery aneurysms following Kawasaki disease should have a CT coronary angiogram performed in adulthood.

The Mechanical Performance of Re-Bonded and Healed Adhesive Joints Activable through Induction Heating Systems

This work aims to study the healing potential properties of a reversible thermoplastic adhesive. The adhesive is activable by using induction heating systems that can induce thermal heat in the particles throughout the electromagnetic field so they can melt the adhesive for bonding or separation procedures. The healing procedure consists of damaging single lap joint (SLJ) specimens with quasi-static and fatigue tests and then using an inductor to generate an electromagnetic field able to heat the adhesive to its melting point in order to heal the damaged SLJ specimens. SLJ tests were performed on damaged and healed specimens to assess, respectively, the residual mechanical properties of the damaged specimens and the mechanical properties after healing. SLJ tests showed that the healing procedure can completely recover the joint stiffness of the damaged adhesive joints, a huge part of the maximum shear strength and the SLJ absorbed energy. This work shows also the possibility of re-bonding completely failed or separated SLJs by using the same procedure. The mechanical properties of SLJs after healing and re-bonding are compared to the SLJ compared on virgin specimens to assess the recovered mechanical properties.

Thraustochytrids of Mangrove Habitats from Andaman Islands: Species Diversity, PUFA Profiles and Biotechnological Potential

Thraustochytrids are the most promising microbial source for the commercial production of docosahexaenoic acid (DHA) for its application in the human health, aquaculture, and nutraceutical sectors. The present study isolated 127 thraustochytrid strains from mangrove habitats of the south Andaman Islands, India to study their diversity, polyunsaturated fatty acids (PUFAs), and biotechnological potential. The predominant strains were identified as belonging to two major genera (Thraustochytrium, Aurantiochytrium) based on morphological and molecular characteristics. The strain ANVKK-06 produced the maximum biomass of 5.42 g·L^-1, while ANVKK-03 exhibited the maximum total lipid (71.03%). Omega-3 PUFAs such as eicosapentaenoic acid (EPA) accumulated up to 11.03% in ANVKK-04, docosapentaenoic acid (DPA) up to 8.65% in ANVKK-07, and DHA up to 47.19% in ANVKK-06. ANVKK-06 showed the maximum scavenging activity (84.79 ± 2.30%) while ANVKK-03 and ANVKK-10 displayed the highest antibacterial activity against human and fish pathogens, S. aureus (18.69 ± 1.2 mm) and V. parahaemolyticus (18.31 ± 1.0 mm), respectively. All strains were non-toxic as evident by negative blood agar hemolysis, thus, the thraustochytrids are suggested to be a potential source of DHA for application in the health care of human and fish.

The Role of CEUS in the Evaluation of Thyroid Cancer: From Diagnosis to Local Staging

Ultrasound often represents the first diagnostic step for thyroid nodule evaluation in clinical practice, but baseline US alone is not always effective enough to achieve thyroid nodule characterization. In the last decades new ultrasound techniques, such as CEUS, have been introduced to evaluate thyroid parenchyma as recommended by EFSUMB guidelines, for use in clinical research field, although its role is not yet clear. Several papers show the potential utility of CEUS in the differential diagnosis of benign and malignant thyroid nodules and in the analysis of lymph node involvement in neoplastic pathology. Therefore, we carried out an evaluation of the literature concerning the role of CEUS in three specific areas: the characterization of the thyroid nodule, the evaluation of minimally invasive treatment and loco-regional staging of the lymph node in proven thyroid cancer. According to evidence reported, CEUS can also play an operative role in nodular thyroid pathology as it is able to guide ablation procedures on thyroid nodule and metastatic lymph nodes, to assess the radicality of surgery, to evaluate disease relapse at the level of the margins of ablated regions and to monitor the clinical evolution of necrotic areas in immediate post-treatment setting.

Effect of Rare-Earth Ions on the Optical and PL Properties of Novel Borosilicate Glass Developed from Agricultural Waste

There is considerable attention devoted to the use of agricultural waste as a raw material substitute for commercial silica in the development of borosilicate glasses doped with rare earth oxides. Here, we present a novel structure for borosilicate glasses made from rice husk ash with a 25% molar ratio of extracted SiO₂ and doped with neodymium (GRN) or dysprosium (GRD). Adding rare earth oxides to borosilicate glasses by the melt quenching method enhanced optical transmission due to the presence of their tetrahedral geometries. GRN samples showed few bands near zero, which constitutes good utility for band rejection filters in image devices, and the samples exhibited energy values ranging from 3.03 to 3.00 eV before and after gamma irradiation. Optical transmissions of GRD samples showed peaks at 25,974, 22,172, 13,333, 11,273, 9302, 7987, and 6042 cm^-1. Deterioration in transmittance was observed when the investigated samples were exposed to irradiation doses of 20 and 50 kGy in the wavenumber range of 12,500 to 50,000 cm^-1; however, different behaviors after irradiation with 50 kGy caused an increase in transparency in comparison to 20 kGy irradiation, which was pronounced for higher wavenumbers (greater than 12,500 cm^-1). Photoluminescence emission and excitation spectra of the glass-doped Nd³⁺ (GRN) and glass-doped Dy³⁺ (GRD) samples were determined. GRD exhibited emission in the blue and yellow regions of the visible spectrum, which gave a white flash of light. Chromaticity coordinate (CIE) measurements of GRD samples indicated the origin of its luminous color relative to the standard white light region.

Value of Conventional Ultrasonography with Contrast-Enhanced Ultrasonography in the Differential Diagnosis of Partial Cystic Thyroid Nodules

The value of contrast-enhanced ultrasonography (CEUS) in the diagnosis of malignant partial cystic thyroid nodules (PCTNs) remains unclear. Thus, in the present study, the data of patients with pathologically proven PCTNs who underwent CEUS in the Chinese PLA General Hospital from January 2016 to February 2019 were retrospectively reviewed, and the imaging characteristics of benign and malignant PCTNs were compared. A total of 177 PCTNs were enrolled in this study, including 58 (32.7%) malignant nodules and 119 (67.2%) benign nodules. Six characteristics significantly differed between malignant PCTNs and benign PCTNs in univariate comparison: position of the solid portion (χ² = 17.937, p < 0.001), microcalcifications (χ² = 81.382, p < 0.001), boundaries (χ² = 45.486, p < 0.001), echogenicity (χ² = 11.152, p = 0.004), intensity of enhancement (χ² = 40.656, p < 0.001) and uniformity of enhancement (χ² = 19.933, p < 0.001). Among these, microcalcifications, boundaries, position of the solid portion, and uniformity of enhancement were independent risk factors in the multivariate comparison. A logistic regression model for predicting benign and malignant PCTNs was established with a sensitivity, specificity, positive predictive value, negative predictive value and accuracy of 89.0% (95% confidence interval [CI]: 0.788-0.961), 91.0% (95% CI: 0.830-0.946), 81.0% (95% CI: 0.715-0.881), 95.0% (95% CI: 0.892-0.974) and 90.0% (95% CI: 0.844-0.938), respectively. The area under the receiver operating characteristic curve was 0.967 (95% CI: 0.944-0.990), which was significantly higher than that of conventional ultrasound only (0.747, 95% CI: 0.663-0.831, Z = 2.090, p = 0.0366). CEUS can be used in the diagnosis of PCTNs, and the four characteristics of malignant PCTNs proven by our study were microcalcifications, unclear boundaries, eccentric distributions of the solid parts and heterogeneous enhancement.

Contrast-Enhanced Ultrasound in the Differential Diagnosis and Risk Stratification of ACR TI-RADS Category 4 and 5 Thyroid Nodules With Non-Hypovascular

Objective

This study aims to investigate the value of contrast-enhanced ultrasound (CEUS) in the differential diagnosis and risk stratification of ACR TI-RADS category 4 and 5 thyroid nodules with non-hypovascular.

Methods

From January 2016 to December 2019 in our hospital, 217 ACR TI-RADS category 4 and 5 nodules with non-hypovascular in 210 consecutive patients were included for a derivation cohort. With surgery and/or fine-needle aspiration (FNA) as a reference, conventional ultrasound (US) features and CEUS features were analyzed. Multivariate logistic regression analysis was used to screen the independent risk factors and establish a risk predictive model. Between January 2020 and March 2021, a second cohort of 100 consecutive patients with 101 nodules were included for an external validation cohort. The model was converted into a simplified risk score and was validated in the validation cohort. The area under the receiver operating characteristic curves (AUC) were used to assess the models’ diagnostic performance.

Results

Micro-calcification, irregular margin, earlier wash-out, centripetal enhancement, and absence of ring enhancement were independent risk factors and strongly discriminated malignancy in the derivation cohort (AUC = 0.921, 95% CI 0.876–0.953) and the validation cohort (0.900, 0.824–0.951). There was no significant difference (P = 0.3282) between the conventional US and CEUS in differentiating malignant non-hypovascular thyroid nodules, but a combination of them (the predictive model) had better performance than the single method (all P <0.05), with a sensitivity of 87.0%, specificity of 86.2%, and accuracy of 86.6% in the derivation cohort. The risk score based on the independent risk factors divided non-hypovascular thyroid nodules into low-suspicious (0–3 points; malignancy risk <50%) and high-suspicious (4–7 points; malignancy risk ≥ 50%), the latter with nodule ≥10mm was recommended for FNA. The risk score showed a good ability of risk stratification in the validation cohort. Comparing ACR TI-RADS in screening suitable non-hypovascular nodules for FNA, the risk score could avoid 30.8% benign nodules for FNA.

Conclusions

CEUS is helpful in combination with conventional US in differentiating ACR TI-RADS category 4 and 5 nodules with non-hypovascular. The risk score in this study has the potential to improve the diagnosis and risk stratification of non-hypovascular thyroid nodules.

Improving the diagnosis of AUS/FLUS thyroid nodules using an algorithm with combination of BRAFV600E mutation analysis and ultrasound pattern-based risk stratification

PURPOSE

To propose a diagnostic algorithm for improving the diagnosis of atypia of undetermined significance or follicular lesion of undetermined significance (AUS/FLUS) thyroid nodules.

METHODS

This study retrospectively enrolled 77 consecutive patients with 81 AUS/FLUS nodules who underwent preoperative BRAFV600E mutation analysis. A new diagnostic algorithm was proposed that BRAFV600E mutation analysis for the Fine-needle aspiration cytology specimen was firstly carried out, in which positive BRAFV600E mutation indicated malignancy and classification of the nodules with negative BRAFV600E mutation was further performed based on ultrasound pattern-based risk stratification of American Thyroid Association Guidelines. The diagnostic performance of the new diagnostic algorithm was evaluated.

RESULTS

The sensitivity, specificity, positive predictive value, negative predictive value, accuracy, and area under the receiver operating characteristic curve (AUROC) of new diagnostic algorithm were 94.6%, 84.0%, 91.4%, 86.9%, 90.1%, and 0.893, respectively. The proposed diagnostic algorithm significantly increased the diagnostic performances (AUROC: 0.893 vs. 0.837 and 0.795), sensitivity (94.6% vs. 71.4% and 75.0%), and accuracy (90.1% vs. 79.0% and 77.8%) compared with BRAFV600E mutation analysis alone and ultrasound pattern-based risk stratification alone (all P < 0.05).

CONCLUSION

The proposed diagnostic algorithm is helpful for improving the diagnosis of AUS/FLUS nodules, which might be as a routine approach.

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.

Comparative Diagnostic Accuracy of Contrast-Enhanced Ultrasound and Shear Wave Elastography in Differentiating Benign and Malignant Lesions: A Network Meta-Analysis

Background: We performed a network meta-analysis to compare the diagnostic accuracy of contrast-enhanced ultrasound (CEUS) and shear wave elastography (SWE) in differentiating benign and malignant lesions in different body sites.

Methods: A computerized literature search of Medline, Embase, SCOPUS, and Web of Science was performed using relevant keywords. Following data extraction, we calculated sensitivity, specificity, positive likelihood ratio (LR), negative LR, and diagnostic odds ratio (DOR) for CEUS, and SWE compared to histopathology as a reference standard. Statistical analyses were conducted by MetaDiSc (version 1.4) and R software (version 3.4.3).

Results: One hundred and fourteen studies (15,926 patients) were pooled in the final analyses. Network meta-analysis showed that CEUS had significantly higher DOR than SWE (DOR = 27.14, 95%CI [2.30, 51.97]) in breast cancer detection. However, there were no significant differences between CEUS and SWE in hepatic (DOR = −6.67, 95%CI [−15.08, 1.74]) and thyroid cancer detection (DOR = 3.79, 95%CI [−3.10, 10.68]). Interestingly, ranking analysis showed that CEUS achieved higher DOR in detecting breast and thyroid cancer, while SWE achieved higher DOR in detecting hepatic cancer. The overall DOR for CEUS in detecting renal cancer was 53.44, 95%CI [29.89, 95.56] with an AUROC of 0.95, while the overall DOR for SWE in detecting prostate cancer was 25.35, 95%CI [7.15, 89.89] with an AUROC of 0.89.

Conclusion: Both diagnostic tests showed relatively high sensitivity and specificity in detecting malignant tumors in different organs. Network meta-analysis showed that CEUS had higher diagnostic accuracy than SWE in detecting breast and thyroid cancer, while SWE had higher accuracy in detecting hepatic cancer. However, the results were not statistically significant in hepatic and thyroid malignancies. Further head-to-head comparisons are needed to confirm the optimal imaging technique to differentiate each cancer type.

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.

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.

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.

Logistic regression analysis of conventional ultrasonography, strain elastosonography, and contrast-enhanced ultrasound characteristics for the differentiation of benign and malignant thyroid nodules

The aim of the study is to screen the significant sonographic features by logistic regression analysis and fit a model to diagnose thyroid nodules. A total of 525 pathological thyroid nodules were retrospectively analyzed. All the nodules underwent conventional ultrasonography (US), strain elastosonography (SE), and contrast -enhanced ultrasound (CEUS). Those nodules' 12 suspicious sonographic features were used to assess thyroid nodules. The significant features of diagnosing thyroid nodules were picked out by logistic regression analysis. All variables that were statistically related to diagnosis of thyroid nodules, at a level of p < 0.05 were embodied in a logistic regression analysis model. The significant features in the logistic regression model of diagnosing thyroid nodules were calcification, suspected cervical lymph node metastasis, hypoenhancement pattern, margin, shape, vascularity, posterior acoustic, echogenicity, and elastography score. According to the results of logistic regression analysis, the formula that could predict whether or not thyroid nodules are malignant was established. The area under the receiver operating curve (ROC) was 0.930 and the sensitivity, specificity, accuracy, positive predictive value, and negative predictive value were 83.77%, 89.56%, 87.05%, 86.04%, and 87.79% respectively.

Analysis of arterial dynamic micro-vascularization with contrast-enhanced ultrasound (CEUS) in thyroid lesions using external perfusion software: First results

AIM

To determine different perfusion characteristics of histo-pathologically proven adenomas and carcinomas of the thyroid gland with CEUS and perfusion software.

MATERIAL AND METHODS

Retrospective perfusion analysis of 25 patients with carcinomas and 41 cases of adenomas of the thyroid gland (30 males, 36 females; aged 18 - 85 years, mean 56 years). All cases were histologically analyzed. Perfusion analysis was independently performed using external perfusion software (VueBox®). TTP, mTT, Peak and Rise time were calculated.

RESULTS

Lesions' sizes ranged from 0.2 to 10.2 cm in carcinomas (mean 2.18 cm), and from 0.6 to 5.0 cm in adenomas (mean 2.25 cm). In 20 out of 25 carcinomas that were evaluated with CEUS, a complete wash-out in the late venous phase was found. Adenomas showed wash-out at the border.Perfusion analysis in VueBox® revealed some parameters which tend to show differences between adenomas and carcinomas, however did not reach the level of significance.Median Peak in carcinomas was highest at the margins (2945 rU), and lowest in the surroundings (1110 rU). Mean Transit Time (mTT) values showed no differences between center, margin and surrounding.In adenomas healthy tissue showed higher mTT values compared to the center (24.6 vs. 20.7 sec). Median Peak was highest in the surrounding tissue and lowest in the margins (1999 vs. 1129 rU). No statistical differences could be found in the comparisons.

CONCLUSION

CEUS with perfusion analysis offers new possibilities for the dynamic evaluation of micro-vascularization in thyroid adenomas and carcinomas. Using VueBox® the perfusion analysis of the arterial phase provides new parameters that help determine a lesion's malignancy or benignity. However a final assessment regarding malignancy and benignity of thyroid lesions using only CEUS and perfusion analysis of the arterial phase is not yet possible.

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.

Primary follicular thyroid carcinoma metastasis to the kidney and widespread dissemination: A case report

Distant metastases are more common in follicular thyroid carcinoma (FC) than in papillary thyroid carcinoma. However, FC metastasis to the kidney with eggshell calcification, as observed in the present case, is rare. The current report presents a case of a 67-year-old woman exhibiting a solitary tumor in the mid pole of the left kidney. Radical nephrectomy was performed, as the tumor was diagnosed as a primary renal carcinoma using contrast-enhanced computed tomography. Once the tumor was confirmed to be FC, total thyroidectomy was performed. Following administration of an oral therapeutic dose of 100 mCi ¹³¹I, functional imaging demonstrated the presence of multifocal metastases in the chest and abdomen. Euthyrox^® was prescribed orally to aid normal thyroid function. Follow-up 6 months later using radionuclide imaging demonstrated the disappearance of the multifocal metastases in the chest and abdomen. The distant metastasis of FC may represent the initial symptom of the primary lesion, which was neglected. Ultrasound is an effective method to examine nodules located on the thyroid.