Contrast-enhanced ultrasound image sequences based on radiomics analysis for diagnosis of metastatic cervical lymph nodes from thyroid cancer.

Background: Thyroid cancer (TC) prone to cervical lymph node (CLN) metastasis both before and after surgery. Ultrasonography (US) is the first-line imaging method for evaluating the thyroid gland and CLNs. However, this assessment relies mainly on the subjective judgment of the sonographer and is very much dependent on the sonographer's experience. This prospective study was designed to construct a machine learning model based on contrast-enhanced ultrasound (CEUS) videos of CLNs to predict the risk of CLN metastasis in patients with TC. Methods: Patients who were proposed for surgical treatment due to TC from August 2019 to May 2020 were prospectively included. All patients underwent US of CLNs suspected of metastasis, and a 2-minute imaging video was recorded. After target tracking, feature extraction, and feature selection through the lymph node imaging video, three machine learning models, namely, support vector machine, linear discriminant analysis (LDA), and decision tree (DT), were constructed, and the sensitivity, specificity, and accuracy of each model for diagnosing lymph nodes were calculated by leave-one-out cross-validation (LOOCV). Results: A total of 75 lymph nodes were included in the study, with 42 benign cases and 33 malignant cases. Among the machine learning models constructed, the support vector machine had the best diagnostic efficacy, with a sensitivity of 93.0%, a specificity of 93.8%, and an accuracy of 93.3%. Conclusions: The machine learning model based on US video is helpful for the diagnosis of whether metastasis occurs in the CLNs of TC patients.

The electric field cavity array effect of 2D nano-sieves.

For the upsurge of high breakdown strength ([Formula: see text]), efficiency ([Formula: see text]), and discharge energy density ([Formula: see text]) of next-generation dielectrics, nanocomposites are the most promising candidates. However, the skillful regulation and application of nano-dielectrics have not been realized so far, because the mechanism of enhanced properties is still not explicitly apprehended. Here, we show that the electric field cavity array in the outer interface of nanosieve-substrate could modulate the potential distribution array and promote the flow of free charges to the hole, which works together with the intrinsic defect traps of active Co3O4 surface to trap and absorb high-energy carriers. The electric field and potential array could be regulated by the size and distribution of mesoporous in 2-dimensional nano-sieves. The poly(vinylidene fluoride-co-hexafluoropropylene)-based nanocomposites film exhibits an [Formula: see text] of 803 MV m-1 with up to 80% enhancement, accompanied by high [Formula: see text] = 41.6 J cm-3 and [Formula: see text]≈ 90%, outperforming the state-of-art nano-dielectrics. These findings enable deeper construction of nano-dielectrics and provide a different way to illustrate the intricate modification mechanism from macro to micro.

Partially cystic thyroid cancer on conventional and elastographic ultrasound: a retrospective study and a machine learning-assisted system.

BACKGROUND: Thyroid carcinoma constitutes the vast majority of all thyroid cancer, most of which is the solid nodule type. No previous studies have examined combining both conventional and elastic sonography to evaluate the diagnostic performance of partially cystic thyroid cancer (PCTC). This retrospective study was designed to evaluate differentiation of PCTC from benign partially cystic nodules with a machine learning-assisted system based on ultrasound (US) and elastography. METHODS: Patients with suspicious partially cystic nodules and finally confirmed were included in the study. We performed conventional US and real-time elastography (RTE). The US features of nodules were recorded. The data set was entered into 6 machine-learning algorithms. Sensitivity, specificity, accuracy, and area under the curve (AUC) were calculated. RESULTS: A total of 177 nodules were included in this study. Among these nodules, 81 were malignant and 96 were benign. Wreath-shaped feature, micro-calcification, and strain ratio (SR) value were the most important imaging features in differential diagnosis. The random forest classifier was the best diagnostic model. CONCLUSIONS: US features of PCTC exhibited unique characteristics. Wreath-shaped partially cystic nodules, especially with the appearance of micro-calcifications and larger SR value, are more likely to be malignant. The random forest classifier might be useful to diagnose PCTC.

[The Characteristics of Ultrasonography and Thermal Tomography in Various Molecular Subtypes of Breast Cancer].

OBJECTIVE: To explore the relationship between the imaging features of ultrasonography and thermal tomography and molecular subtypes of breast cancer. METHODS: 404 female breast cancer patients with complete imaging data and pathological findings from January 2014 to June 2017 were reviewed in the West China Hospital of Sichuan University. Breast cancer pathological molecules were classified into Luminal A like type, Luminal B like type, human epidermal growth receptor-2 (HER-2) overexpression type and Basal like type according to the expression of various immune markers. The correlation of ultrasonographic BI-RADS signs, thermal tomography characteristics and immunohistochemical results of breast cancer was analyzed. RESULTS: Breast cancer lesions with regular morphology, sharp margins, and enhanced posterior echo were more common in Basal like type; Microcalcification was more likely tend to appear in HER-2 expression breast cancer than other subtypes; The q-r curve of Luminal A like breast cancer was nearly 30°, and that was more common between 30°and 45° of HER-2 expression and Basal like breast cancer；The ratio of vertical and horizontal ≥1 of tumors and limited lymph node metastasis could not be used for distinguishing between different subtypes. CONCLUSION: Different molecular subtypes of breast cancer may behave routine ultrasound and thermal tomography imaging features.

[Breast Thermal Tomography and High Frequency Ultrasound Imaging in Predicting Breast Cancer: a Preliminary Study].

OBJECTIVE: To determine the clinical value of breast thermal tomography and high frequency ultrasound imaging in diagnosing breast cancer. METHODS: Breast thermal tomography and high frequency ultrasound imaging were performed in 298 patients with breast lumps. The results were compared with pathological diagnosis. RESULTS: The ultrasound imaging had a sensitivity, specificity and the area under the curve (AUC) of 99.02%, 62.78% and 0.814, respectively, compared with 83.33%, 83.16% and 0.830 of thermal tomography, for diagnosing breast cancer. The two imaging results showed statistical significance in the test of non-inferiority (P < 0.001). A combination of the two imaging results produced a sensitivity, specificity and AUC of 83.33%, 89.79% and 0.866, respectively. CONCLUSION: Thermal tomography is not inferior to ultrasonography in detecting breast cancer. The two combined can improve specificity and accuracy of the diagnosis of breast cancer.

Value of contrast-enhanced ultrasonography in the differential diagnosis of enlarged lymph nodes: a meta-analysis of diagnostic accuracy studies.

OBJECTIVE: To evaluate the diagnostic accuracy of contrast-enhanced ultrasonography (CEUS) in differentiating between benign and malignant enlarged lymph nodes using meta-analysis. MATERIALS AND METHODS: Pubmed, Embase, SCI and Cochrane databases were searched for studies (up to September 1, 2014) reporting the diagnostic performance of CEUS in discriminating between benign and malignant lymph nodes. Inclusion criteria were: prospective study; histopathology as the reference standard; and sufficient data to construct 2?2 contingency tables. Methodological quality was assessed using Quality Assessment of Diagnostic Accuracy Studies-2 (QUADAS-2). Patient clinical characteristics, sensitivity and specificity were extracted. The summary receiver operating characteristic curve was used to examine the accuracy of CEUS. A meta-analysis was performed to evaluate the clinical utility in identification of benign and malignant lymph nodes. Sensitivity analysis was performed after omitting outliers identified in a bivariate boxplot and publication bias was assessed with Egger testing. RESULTS: The pooled sensitivity, specificity and AUROC were 0.92 (95%CI, 0.85-0.96), 0.91 (95%CI, 0.82-0.95) and 0.97 (95%CI, 0.95-0.98), respectively. After omitting 3 outlier studies, heterogeneity decreased. Sensitivity analysis demonstrated no disproportionate influences of individual studies. Publication bias was not significant. CONCLUSIONS: CEUS is a promising diagnostic modality in differentiating between benign and malignant lymph nodes and can potentially reduce unnecessary fine-needle aspiration biopsies of benign nodes.

[Analysis of urine screening results for school-age children in Zhucheng City of Shandong Province of China in 2013].

OBJECTIVE: To study the significance of urine screening for school-age children by analyzing urine screening results of school-age children from Zhucheng City, Shandong Province, China, in 2013. METHODS: A total of 37 344 school-age children were randomly selected from children 6 to 12 years of age in Zhucheng City. Morning urine was tested by routine screening test, and the children who tested positive were re-tested after two weeks. RESULTS: There were 2 388 children (6.39%) tested positive in the first screening, and 388 children (1.04%) tested positive again in the second screening. The positive rates in the first and second screening tests were 9.52% and 2.01%, respectively, in girls, which were significantly higher than those in boys (3.79% and 0.23%, respectively; P<0.05). Among the children who had positive test results in the second screening, 302 (0.81%) were diagnosed with urinary system diseases. CONCLUSIONS: Urine screening is an effective way for the early detection of some occult kidney diseases, which provides great benefits for early prevention and treatment of kidney diseases in children.

[The perfusion pattern of lymphadenopathy in contrast-enhanced ultrasonograph. under different reference conditions ].

OBJECTIVE: To determine the perfusion pattern of lymphadenopathy in contrast-enhanced ultrasonography (CEUS) under different reference conditions. METHODS: The CEUS perfusion patterns of 78 superficial lymph node lesions were compared with their pathology results. Time-intensity curves were used for comparison between benign and malignant lymph nodes. RESULTS: Inhomogeneous hyperenhancement was the main perfusion pattern (7/17, 41. 2%) in metastatic lymph nodes; compared with homogeneous hyperenhancement (2/4, 50. 0%) in lymphoma, homogeneous hyperenhancement and isoenhancement (6/52, 11. 5%) in reactive lymph nodes, and circle enhancement (2/4,50. 0%) in tuberculosis. Benign lymph nodes showed different mean value, peak intensity and area under the curve compared with their surrounding arteries (P<0. 05). But the differences in mean value, rise time, time to peak, peak intensity and the area under the curve between benign lymphadenopathy and their surrounding tissues were not statistically significant (P>0. 05). Malignant lymph nodes showed different mean value and peak intensity compared with their surrounding arteries and tissues (P<0. 05). The differences in time to peak between malignant lymph nodes and their surrounding tissues were also statistically significant (P< 0. 05). CONCLUSION: Different CEUS perfusion patterns are associated with different types of lymph node lesions. Time intensity curves with surrounding tissues as reference condition offer great values for the differential diagnosis of superficial lymphadenopathy.