Nodule or pseudonodule? Differentiation in Hashimoto's thyroiditis with sonoelastography

Association of autoimmune thyroid disease with type 1 diabetes mellitus and its ultrasonic diagnosis and management

As a common hyperglycemic disease, type 1 diabetes mellitus (T1DM) is a complicated disorder that requires a lifelong insulin supply due to the immune-mediated destruction of pancreatic β cells. Although it is an organ-specific autoimmune disorder, T1DM is often associated with multiple other autoimmune disorders. The most prevalent concomitant autoimmune disorder occurring in T1DM is autoimmune thyroid disease (AITD), which mainly exhibits two extremes of phenotypes: hyperthyroidism [Graves' disease (GD)] and hypo-thyroidism [Hashimoto's thyroiditis, (HT)]. However, the presence of comorbid AITD may negatively affect metabolic management in T1DM patients and thereby may increase the risk for potential diabetes-related complications. Thus, routine screening of thyroid function has been recommended when T1DM is diagnosed. Here, first, we summarize current knowledge regarding the etiology and pathogenesis mechanisms of both diseases. Subsequently, an updated review of the association between T1DM and AITD is offered. Finally, we provide a relatively detailed review focusing on the application of thyroid ultrasonography in diagnosing and managing HT and GD, suggesting its critical role in the timely and accurate diagnosis of AITD in T1DM.

Incidentally discovered papillary thyroid microcarcinoma in patients undergoing thyroid surgery for benign disease

INTRODUCTION

The incidence of thyroid carcinoma has grown significantly over the last few decades. A possible explanation is the increased diagnosis of small thyroid microcarcinoma (TMc). TMc reach a maximum diameter of ≤1 cm, identified during histopathology examination following a thyroidectomy performed for reasons not pertaining to malignancy. This study aims to investigate the prevalence of papillary thyroid microcarcinoma (PTMc) according to the benign pathology that refers patients to surgery and its trend evolution.

METHODS

Retrospective cohort analysis of 1815 patients who underwent total thyroidectomy for non-malignant diseases in the 2005-2020 period.

RESULTS

The mean age of the subjects was 53.5 years, with a higher proportion of women (1481, 82.1%). A total of 167 PTMc (9.3%) were incidentally discovered. A multivariate logistic regression analysis was performed, showing no differences in prevalence according to sex or age in patients with PTMc compared to final benign histology. Multinodular goiter increases the risk of PTMc with an odds ratio of 2.2 (p = 0.001) compared to Hashimoto's thyroiditis and Graves' disease (GD). There is a statistically significant increase in the incidence of PTMc in the group operated in the 2017-2020 vs. 2005-2008 period (p = 0.005).

CONCLUSION

The overall prevalence of PTMc in patients who underwent thyroid surgery for the benign disease was 9.3%. Thyroid nodular hyperplasia was the most frequent benign pathology associated with PTMc compared to Hashimoto's or GD. Gender and age were not correlated with the prevalence of TMc. Over the years, surgical findings of PTMc have grown, particularly in the 2017-2020 period.

Role of ultrasound and Doppler findings as a predictor of thyroid hormonal levels in cases of Hashimoto thyroiditis

Background

Chronic lymphocytic thyroiditis or Hashimoto’s thyroiditis (HT) is a common form of organ specific autoimmune disease mediated by anti-thyroid autoantibodies. Ultrasound including Doppler is helpful diagnostic tool in the diagnosis of Hashimoto’s thyroiditis. This study aimed to evaluate the ultrasound and Doppler characters of Hashimoto thyroiditis and to analyze the relationship between these ultrasound, Doppler features and thyroid hormones level.

Results

Thyroid gland sonographic parenchymal abnormalities (septations, undulation, micronodularity, gland hyper vascularity, hypoechogenicity, sizable nodules as well as enlarged para-tracheal lymph nodes) were significantly higher in Hashimoto cases compared to control group (P value is < 0.001). Undulation of thyroid gland margin was the most sensitive sonographic sign seen in about 72% of studied cases. Thyroid stimulating hormone (TSH) level was significantly high in cases with grade 2 echogenicity compared to cases with grade 0 and grade 1 echogenicity and was significantly high in cases with para-tracheal abnormal enlarged lymph nodes (p < 0.05). TSH & thyroxine (T4) levels were significantly high in cases with high gland vascularity in Doppler study (p < 0.05).

Conclusions

Ultrasound is a very good diagnostic tool in HT with established signs. It can suggest hypothyroidism (high TSH) in cases of grade 2 parenchymal echogenicity, high vascularity and para-tracheal lymph nodes enlargement. These finding could be helpful in patient management and can contribute in better understanding the disease progression.

Thyroid nodules in childhood-onset Hashimoto's thyroiditis: Frequency, risk factors, follow-up course and genetic alterations of thyroid cancer

OBJECTIVE

We evaluated the frequency, risk factors and the follow-up outcomes of thyroid nodules, and genetic alterations in thyroid cancer, in youth with childhood-onset Hashimoto thyroiditis (HT) residing in an iodine-sufficient country.

DESIGN

A retrospective cohort study.

PATIENTS AND MEASUREMENTS

A total of 213 patients (194 females, mean age 10.6 years at the time of HT diagnosis) were ultrasonographically evaluated. Thyroid nodules were categorized using the Korean Thyroid Imaging Reporting and Data System (K-TIRADS) and the American College of Radiology Thyroid Imaging Reporting and Data System (ACR-TI-RADS).

RESULTS

Thyroid nodules were detected in 40 (18.8%) patients over a median follow-up period of 3.4 years, usually after the onset of puberty. A family history of thyroid disease (hazard ratio 2.1, p = .031) was predictive of thyroid nodule detection. Papillary thyroid carcinoma (PTC) was diagnosed in 9 (4.2% of all and 22.5% of nodule-positive patients). The malignant nodules had a higher K-TIRADS or ACR-TI-RADS risk level compared with benign nodules (p < .01 for both). Genetic alterations were revealed in 7 (BRAF^V600E in 6 and RET-ERC1 fusion in 1) of the eight available tumour tissue samples. None showed evidence of disease over a median follow-up period of 3.4 years.

CONCLUSIONS

The nodule detection rate was 18.8%, with a 22.5% risk of malignancy among the detected nodules in childhood-onset HT patients, showing increased risk in those with a family history. Additional large-scale studies are required to evaluate the usefulness of K-TIRADS or ACR-TI-RADS risk level for the differentiation of paediatric thyroid nodules.

Relationship between TSHR, BRAF and PIK3CA gene copy number variations and thyroid nodules

PURPOSE

This study aims to investigate the relationship between the TSHR, BRAF, and PIK3CA gene copy number variations (CNVs) and thyroid nodules by analyzing gene CNVs, and to explore the interaction between iodine status and the above genes CNVs in the occurrence of thyroid nodules.

METHODS

Three hundred and ninety-five subjects were selected from 3 regions with different iodine status in Shanxi Province of China, including 192 patients with thyroid nodules and 203 healthy controls. The basic information about subjects had been obtained through a questionnaire. B ultrasound was utilized to check thyroid nodules. Blood and urine samples were harvested to detect the thyroid function and urinary iodine concentration. Real-time quantitative polymerase chains reaction (RT-PCR) served to detect CNVs in DNA from human blood.

RESULTS

There was an association between TSHR gene CNV and thyroid nodules (χ² = 8.403, P = 0.004). The prevalence of BRAF and PIK3CA gene CNVs was not statistically significant between the case group and the control group. Differences in the TSHR gene CNV rates for cases of the 3 areas were statistically significant (χ² = 10.072, P = 0.007). No statistical difference in the prevalence rates of the 3 genes CNVs between diverse characteristics of thyroid nodules was observed. UIC > 300 μg/L (OR = 1.74, 95% CI: 1.02-2.96, P = 0.041) and TSHR gene CNV (OR = 3.53, 95% CI: 1.40-8.92, P = 0.008) were risk factors for thyroid nodules. There was no significant interaction between the UIC and the examined genes CNVs.

CONCLUSIONS

TSHR gene CNV and high urinary iodine levels can increase the risk of thyroid nodules. But the interactions between the 3 above genes CNVs and iodine nutrition were not found in the occurrence of thyroid nodules.

Intelligent Diagnosis of Thyroid Ultrasound Imaging Using an Ensemble of Deep Learning Methods

Background and Objectives: At present, thyroid disorders have a great incidence in the worldwide population, so the development of alternative methods for improving the diagnosis process is necessary. Materials and Methods: For this purpose, we developed an ensemble method that fused two deep learning models, one based on convolutional neural network and the other based on transfer learning. For the first model, called 5-CNN, we developed an efficient end-to-end trained model with five convolutional layers, while for the second model, the pre-trained VGG-19 architecture was repurposed, optimized and trained. We trained and validated our models using a dataset of ultrasound images consisting of four types of thyroidal images: autoimmune, nodular, micro-nodular, and normal. Results: Excellent results were obtained by the ensemble CNN-VGG method, which outperformed the 5-CNN and VGG-19 models: 97.35% for the overall test accuracy with an overall specificity of 98.43%, sensitivity of 95.75%, positive and negative predictive value of 95.41%, and 98.05%. The micro average areas under each receiver operating characteristic curves was 0.96. The results were also validated by two physicians: an endocrinologist and a pediatrician. Conclusions: We proposed a new deep learning study for classifying ultrasound thyroidal images to assist physicians in the diagnosis process.

False-Positive Malignant Diagnosis of Nodule Mimicking Lesions by Computer-Aided Thyroid Nodule Analysis in Clinical Ultrasonography Practice

This study aims to test computer-aided diagnosis (CAD) for thyroid nodules in clinical ultrasonography (US) practice with a focus towards identifying thyroid entities associated with CAD system misdiagnoses. Two-hundred patients referred to thyroid US were prospectively enrolled. An experienced radiologist evaluated the thyroid nodules and saved axial images for further offline blinded analysis using a commercially available CAD system. To represent clinical practice, not only true nodules, but mimicking lesions were also included. Fine needle aspiration biopsy (FNAB) was performed according to present guidelines. US features and thyroid entities significantly associated with CAD system misdiagnosis were identified along with the diagnostic accuracy of the radiologist and the CAD system. Diagnostic specificity regarding the radiologist was significantly (p < 0.05) higher than when compared with the CAD system (88.1% vs. 40.5%) while no significant difference was found in the sensitivity (88.6% vs. 80%). Focal inhomogeneities and true nodules in thyroiditis, nodules with coarse calcification and inspissated colloid cystic nodules were significantly (p < 0.05) associated with CAD system misdiagnosis as false-positives. The commercially available CAD system is promising when used to exclude thyroid malignancies, however, it currently may not be able to reduce unnecessary FNABs, mainly due to the false-positive diagnoses of nodule mimicking lesions.

Ultrasound elastography of the thyroid: principles and current status

Ultrasound (US) elastography has been introduced as a non-invasive technique for evaluating thyroid diseases. This paper presents a detailed description of the technical principles, peculiarities, and limitations of US elastography techniques, including strain elastography and shear-wave elastography. This review was conducted from a clinical perspective, and aimed to assess the usefulness of US elastography for thyroid diseases in specific clinical scenarios. Although its main focus is on thyroid nodules, the applications of US elastography for other thyroid diseases, such as diffuse thyroid diseases and thyroiditis, are also presented. Furthermore, unresolved questions and directions for future research are also discussed.

Natural History of Contralateral Nodules After Lobectomy in Patients With Papillary Thyroid Carcinoma

BACKGROUND

Bilateral thyroid nodularity is considered an indication for total thyroidectomy in papillary thyroid carcinoma (PTC). However, the natural history and outcome of contralateral nodules have never been studied.

OBJECTIVE

To investigate the natural history of nonsuspicious contralateral nodules after lobectomy for PTC.

METHODS

We included patients who had one or more solid nodules (≥3 mm) in the contralateral lobe with benign cytology before surgery or small nonsuspicious nodules per ultrasonography.

RESULTS

One hundred and twelve patients were included. Median age was 57 years, and median size of the PTC (initial lobectomy) was 8 mm (range, 0.5 to 28 mm). On the contralateral side, the median size of nodules was 7 mm (range, 3 to 30 mm). Thirty-three nodules (29%) had fine-needle aspiration (FNA) before surgery, and all were benign. After a median follow-up of 6 years, median growth was zero (range, -20 to 19 mm). Twenty-six nodules (23%) increased ≥3 mm in size (median, 6 mm; range, 4 to 19 mm). Twenty patients (18%) developed new nodules. Twelve patients (11%) underwent completion thyroidectomy for growth (three), suspicious FNA (seven; Bethesda III to V), malignancy (one), or unknown reason (one). Overall, according to the completion thyroidectomy specimen, six patients (5%) were diagnosed with contralateral PTC (five micro-PTCs, one 20 mm), and all were without evidence of disease at the end of follow-up. There were no surgical difficulties or local complications during completion surgery.

CONCLUSIONS

Lobectomy for low-risk patients with a small PTC and nonsuspicious contralateral thyroid nodule(s) is a reliable and safe initial treatment option. In the few patients who required completion thyroidectomy, treatment with surgery and radioiodine was effective.

The Clinical and Pathological Presentation of Thyroid Nodules in Children and the Comparison with Adult Population: Experience of a Single Institution

The clinical and pathological presentation of thyroid nodules among younger and adult patients was compared in an iodine-deficient (ID) region. Data of 3,010 consecutive patients younger than 20 years and 3,010 patients older than 20 years were compared. The proportion of nodular goiters (22.8% versus 39.3%), the ratio of surgically treated nodules (33.2% versus 15.2%), and the proportion of malignant nodules (4.3% versus 2.1%) among diseased patients differed significantly between the two groups (younger versus adult). Nine papillary and 1 medullary carcinoma were found among children, while 15 papillary, 2 follicular, 1 insular, 1 anaplastic, and 1 medullary carcinomas occurred among adults. The ratio of follicular adenoma to hyperplastic nodules (3 : 1 to 1 : 1.67), the proportion of follicular variant (77.8% versus 26.7%), T4 tumors (77.8% versus 33.3%), and tumors with lymph node metastasis (88.9% versus 66.7%) were significantly higher among younger papillary carcinoma patients. No malignancies occurred among spongiform and central type cysts. Similarly to iodine-sufficient regions, more nodules are malignant and carcinomas have a clinically more aggressive presentation in children in comparison with adult patients in ID. Taking the significantly greater proportion of adenomas and the lack of follicular carcinoma into account, a conservative approach has to be considered in follicular tumors among children.

A Clinical Framework to Facilitate Risk Stratification When Considering an Active Surveillance Alternative to Immediate Biopsy and Surgery in Papillary Microcarcinoma

BACKGROUND

The 2015 American Thyroid Association thyroid cancer management guidelines endorse an active surveillance management approach as an alternative to immediate biopsy and surgery in subcentimeter thyroid nodules with highly suspicious ultrasonographic characteristics and in cytologically confirmed very low risk papillary thyroid cancer (PTC). However, the guidelines provide no specific recommendations with regard to the optimal selection of patients for an active surveillance management approach. This article describes a risk-stratified clinical decision-making framework that was developed by the thyroid cancer disease management team at Memorial Sloan Kettering Cancer Center as the lessons learned from Kuma Hospital in Japan were applied to a cohort of patients with probable or proven papillary microcarcinoma (PMC) who were being evaluated for an active surveillance management approach in the United States.

SUMMARY

A risk-stratified approach to the evaluation of patients with probable or proven PMC being considered for an active surveillance management approach requires an evaluation of three interrelated but distinct domains: (i) tumor/neck ultrasound characteristics (e.g., size of the primary tumor, the location of the tumor within the thyroid gland); (ii) patient characteristics (e.g., age, comorbidities, willingness to accept observation); and (iii) medical team characteristics (e.g., availability and experience of the multidisciplinary team). Based on an analysis of the critical factors within each of these domains, patients with probable or proven PTC can then be classified as ideal, appropriate, or inappropriate candidates for active surveillance.

CONCLUSION

Risk stratification utilizing the proposed decision-making framework will improve the ability of clinicians to recognize individual patients with proven or probable PMC who are most likely to benefit from an active surveillance management option while at the same time identifying patients with proven or probable PMC that would be better served with an upfront biopsy and surgical management approach.

Ultrasound characteristics of the thyroid in children and adolescents with goiter: a single center experience

INTRODUCTION

Autoimmune thyroiditis (AIT) is a common cause of goiter in children, and sonographic changes have been reported in more than one-third at presentation. The aim of this study was to evaluate the ultrasound (US) characteristics of the thyroid and the prevalence of thyroid nodules in children and adolescents presenting with goiter in the presence or absence of AIT.

METHODS

A retrospective review was conducted of the US characteristics of 154 children and adolescents aged <18 years of age with goiter from July 2008 to December 2010. US characteristics were analyzed according to each patient's age, sex, thyrotropin (TSH) levels, and thyroid peroxidase antibody titer (TPOAb). Heterogeneity and nodule prevalence were compared between antibody-positive and -negative goiter.

RESULTS

Heterogeneity was more common in TPOAb-positive (59/71, 83%) compared to TPOAb-negative goiter (24/46, 52%; p<0.001), but there was no correlation between the presence of heterogeneity and TPOAb titer within the antibody-positive group. Nodules were equally prevalent in children with (17%) and without (17.4%) TPOAb, and there was no correlation between the serum TSH level or TPOAb titer and the presence of nodules. Papillary thyroid cancer (PTC) was diagnosed in 3/71 with positive TPOAb compared to 1/46 with negative antibodies. Pseudonodules were identified in 11/71 antibody-positive and none of the antibody-negative patients. However, during follow-up, two of these were later identified as nodules and one was PTC.

CONCLUSION

The majority of children and adolescents with goiter had positive TPOAb (71/117). Sonographic heterogeneity was more common among TPOAb-positive patients. However, thyroid nodules and PTC were equally common in both groups. Only 15% of the nodules and none of the PTC were palpable. These data support the utility of thyroid US to detect unsuspected thyroid nodules and PTC in children with goiter. Prospective follow-up studies of children with goiter are needed to formulate recommendations for evaluation with US and fine-needle aspiration.

Elastography Evaluation of Benign Thyroid Nodules in Patients Affected by Hashimoto's Thyroiditis

The aim of the present prospective study was to evaluate the predictive value of elastography in benign thyroid nodules of patients affected by Hashimoto's thyroiditis (HT). From January 2011 to January 2012, 242 nodules in patients affected by HT were submitted to fine needle aspiration cytology (FNAC). All of the patients underwent sonography and elastography performed before FNAC. 230 (95%) nodules were benign, 8 papillary cancers, and 4 follicular lesions. Score 1 was found in 79.1% of benign lesions (sensitivity 79.1%; specificity 66.7%; PPV 97.8%; NPV 14.3%; accuracy 78.5%; p < 0.05). In order to evaluate the outcome of thyroid ultrasound echogenicity in relation to elastography features of nodule(s), all the patients with benign nodules were stratified according to their hypoechoic pattern of thyroid (mild-moderate and severe). Following stratification score 1 was found in 84.2% of benign nodules (sensitivity 75.0%; specificity 88.9%; PPV 27.3%; NPV 98.4%; accuracy 88.2%; p < 0.0001) of patients with a mild-moderate ultrasound thyroid hypoechogenicity, whereas it was found in 60% of benign nodules (p = 0.715) of patients with a marked thyroid hypoechogenicity. Elastography appears to have limited value in detecting thyroid cancer in patients affected by Hashimoto's thyroiditis with severe hypoechoic thyroid tissue.

Roles of ultrasound and power Doppler ultrasound for diagnosis of Hashimoto thyroiditis in anti-thyroid marker-positive euthyroid subjects

PURPOSE

The present study was performed to investigate the contribution of ultrasonographic (US) findings to diagnosis in anti-thyroid marker-positive patients with normal hormone levels among euthyroid subjects with Hashimoto's thyroiditis (HT).

METHODS

Forty premenopausal euthyroid patients with a median age of 32 years (range, 20-44 years) with normal levels of free triiodothyronine (FT3) and free thyroxine (FT4), and elevated anti-thyroid peroxidase (TPO) antibodies were enrolled in this study. A control group of 46 healthy individuals with a median age of 29 years (range, 18-43 years) was composed of randomly selected volunteers. The examinations included basic morphometric (measurement of thyroid gland dimensions in three axes, the volume of each thyroid lobe, and the total thyroid volume), morphological grayscale imaging (echogenicity, nodularity, septations, undulation of the margins, and reactive lymph nodes), and thyroid gland vascularity.

RESULTS

There were no statistically significant differences in morphometric parameters of the thyroid gland between the study and control groups. There were significant differences in the presence of nodularity, undulation of the gland margins, septations inside the glands, infrathyroidal and/or pretracheal reactive lymph nodes, and increased vascularity on power Doppler imaging between the groups. The use of all parameters together yielded a sensitivity of 90%, specificity of 84.8%, positive predictive value (PPV) of 83.7%, negative predictive value (NPV) of 90.7%, and accuracy of 87.2% for diagnosis of HT.

CONCLUSIONS

US and power Doppler US are helpful for the diagnosis of HT in anti-thyroid marker-positive patients with normal thyroid hormone levels.

Ultrasound elastography for the differential diagnosis of nipple retraction

PURPOSE

Nipple retraction is difficult to diagnose radiologically and extremely worrisome for patients. It occurs most commonly due to pathologies such as previous mastitis or an infiltrative malignancy. With this in mind, the goal of this study was to differentiate benign from malignant lesions of nipple retraction, using the differential characteristics of retroareolar area stiffness, observed by means of the new technological modality of ultrasound elastography (USE).

MATERIALS AND METHODS

Nineteen unilateral nipple retraction cases, including five cases of mammary ductal carcinoma posteriorly infiltrated the areola, two cases of Paget disease, and 12 cases of mastitis, were investigated. Imaging findings [gray-scale ultrasound (US) and USE analyses of the breasts' nipple-areolar complex], pathological evaluation, and the results of 4 years of follow-up treatment were obtained. The recorded images were evaluated by two different radiologists, and all data were analyzed statistically.

RESULTS

Statistical analysis showed that there was a strong correlation between the two radiologists' evaluations. The US images were not diagnostic for either the malignant or benign conditions. The correlation between the diagnosis using US and the final diagnosis was calculated as 0.436 (p = 0.006). However, the USE images were more informative since the correlation ratio between the USE results and the final diagnosis was found to be 0.723 (p < 0.001). While the area under the concentration curve (AUC) values that were used for the diagnostic determination of the US results were inconclusive at 0.274 (p < 0.021), the AUC values for USE were significant, with a diagnostic value of 0.866 for all cases (p < 0.01).

CONCLUSION

The USE modality, which is not commonly used in routine practice, has the potential to solve the problem of differentiation of nipple retraction etiologies in the near future.

Standardized Ultrasound Report for Thyroid Nodules: The Endocrinologist's Viewpoint

BACKGROUND

Ultrasonography (US) plays a crucial role in the diagnostic management of thyroid nodules, but its widespread use in clinical practice might generate heterogeneity in ultrasound reports.

OBJECTIVES

The aims of the study were to propose (a) a standardized lexicon for description of thyroid nodules in order to reduce US reports of interobserver variability and (b) a US classification system of suspicion for thyroid nodules in order to promote a uniform management of thyroid nodules.

METHODS

RELEVANT PUBLISHED ARTICLES WERE IDENTIFIED BY SEARCHING MEDLINE AT PUBMED COMBINING THE FOLLOWING SEARCH TERMS: ultrasonography, thyroid, nodule, malignancy, carcinoma, and classification system. Results were supplemented with our data and experience.

RESULTS

A STANDARDIZED US REPORT SHOULD ALWAYS DOCUMENT POSITION, EXTRACAPSULAR RELATIONSHIPS, NUMBER, AND THE FOLLOWING CHARACTERISTICS OF EACH THYROID LESION: shape, internal content, echogenicity, echotexture, presence of calcifications, margins, vascularity, and size. Combining the previous US features, each thyroid nodule can be tentatively classified as: malignant, suspicious for malignancy, borderline, probably benign, and benign.

CONCLUSIONS

We propose a standardized US report and a tentative US classification system that may become helpful for endocrinologists dealing with thyroid nodules in their clinical practice. The proposed classification does not allow to bypass the required cytological confirmation, but may become useful in identifying the lesions with a lower risk of neoplasm.

The value of ultrasound elastography-guided fine-needle aspiration biopsy of thyroid nodules in reducing nondiagnostic results

Fine-needle aspiration biopsy (FNAB) is an important tool for diagnosing thyroid nodules; however, nondiagnostic results are a problem with FNAB. We evaluated the optimal targeting area of thyroid nodules for FNAB by using ultrasound elastography (USE) to reduce nondiagnostic results. Between December 2008 and November 2010, 96 consecutive prospective subjects scheduled to undergo FNAB were included in the study. Initially, the dominant nodule was evaluated with ultrasound, after which USE was performed. FNABs were performed from both the red (hard foci) and the green (soft foci) color-coded areas using the same technique according to the USE maps. The cellularity of all the specimens was evaluated cytopathologically. Nondiagnostic results from the red and green color-coded areas were compared by Chi-square test. In the red color-coded regions on USE images, the diagnostic rate was 76.0 % and the nondiagnostic rate was 24.0 %. In the green color-coded regions on USE images, the diagnostic rate was 53.1 % and the nondiagnostic rate was 46.9 %. Seven nodules were malignant and 89 were benign. Nondiagnostic results were significantly fewer in red color-coded regions (P = 0.0001). USE can help to enhance the cellularity of biopsy of thyroid nodules to reduce the nondiagnostic results if the red color-coded (less elastic or hard) areas are preferred.