Synthesis and Properties of A Strained Triple Nanohoop.

A strained triple nanohoop with a shared central benzene unit is synthesized using a threefold intramolecular ring-closing approach. Among the five possible constitutional isomers, the isomer with the highest D3h symmetry is isolated, the structure of which contains three nanohoop blades and a central hexaphenylbenzene unit. The structure is elucidated using NMR spectroscopy and mass spectrometry. The optical and electrochemical properties are investigated, revealing a moderate fluorescence quantum yield of 40%. A water-soluble nanomaterial is prepared using a nanoparticle encapsulation method, and a fluorescence quantum yield of 10% is retained, which demonstrates the potential of the nanomaterial in biological systems.

S-Shaped Helical Singlet Diradicaloid and Its Transformation to Circumchrysene via a Two-Stage Cyclization.

Polycyclic hydrocarbons with diradical and polyradical characters usually display unique reactivities in ring-cyclization reactions. However, such reactions are rarely used to construct π-extended polycyclic aromatic hydrocarbons. Here, we describe the synthesis of an S-shaped doubly helical singlet diradicaloid compound and its facile transformation into an unprecedented circumchrysene via a two-stage ring cyclization, which includes: (1) an eletrocylization from diradicaloid precursor and (2) a Scholl reaction. The reaction mechanism was investigated through in situ spectroscopic studies, assisted by theoretical calculations. This reaction sequence yields an optically resolved π-extended [5]helicene derivative with a fluorescence quantum yield up to 85% and a circularly polarized luminescence brightness up to 6.05 M-1 cm-1 in the far-red to near-infrared regions. This sequence also yielded a highly delocalized circumchrysene molecule, exhibiting large electron delocalization, moderate fluorescence quantum yield, and multistage redox properties.

Naphthalimide-Annulated [n]Helicenes: Red Circularly Polarized Light Emitters.

Two [n]heliceno-bis(naphthalimides) 1 and 2 (n = 5 and 6, respectively) where two electron-accepting naphthalimide moieties are attached at both ends of helicene core were synthesized by effective two-step strategy, and their enantiomers could be resolved by chiral stationary-phase high-performance liquid chromatography (HPLC). The single-crystal X-ray diffraction analysis of enantiopure fractions of 1 and 2 confirmed their helical structure, and together with experimental and calculated circular dichroism (CD) spectra, the absolute configuration was unambiguously assigned. Both 1 and 2 exhibit high molar extinction coefficients for the S0-S1 transition and high fluorescence quantum yields (73% for 1 and 69% for 2), both being outstanding for helicene derivatives. The red circularly polarized luminescence (CPL) emission up to 615 nm for 2 with CPL brightness (BCPL) up to 66.5 M-1 cm-1 demonstrates its potential for applications in chiral optoelectronics. Time-dependent density functional theory (TD-DFT) calculations unambiguously showed that the large transition magnetic dipole moment |m| of 2 is responsible for its high absorbance dissymmetry (gabs) and luminescence dissymmetry (glum) factor.

Nitrogen-doped polycyclic aromatic hydrocarbons by a one-pot Suzuki coupling/intramolecular SNAr reaction.

We report a new method for the synthesis of nitrogen-doped (N-doped) polycyclic aromatic hydrocarbons (PAHs) by a Suzuki coupling/intramolecular SNAr cascade reaction. A one- or two-fold [3 + 3] naphtho-annulation of halogenated aniline was conducted under Suzuki-Miyaura cross-coupling conditions to yield a series of fully fused N-doped PAHs. In contrast to reported methods to synthesize pyridinic or pyrrolic nitrogen-doped PAHs, our method enables preparation of PAHs doped with graphitic nitrogen, for which few reports are known in the literature. The crystal structure as well as absorption, fluorescence and electrochemical properties of these N-doped PAHs were investigated, which demonstrated the capability of N-doping to adjust optical and electronic properties and alter the LUMO energy level.

Differential diagnosis and feature visualization for thyroid nodules using computer-aided ultrasonic diagnosis system: initial clinical assessment.

BACKGROUND: To assess the diagnostic efficacy of the computer-aided ultrasonic diagnosis system (CAD system) in differentiating benign and malignant thyroid nodules. METHODS: The images of 296 thyroid nodules were included in validation sets. The diagnostic efficacy of the CAD system was compared with that of junior physicians and senior physicians, as well as that of the combination diagnosis of the CAD system with junior physicians. The diagnostic efficacy of the CAD system for different sizes of thyroid nodules was compared. RESULTS: The diagnostic sensitivity and accuracy of the CAD system were higher than those of junior physicians (83.4% vs. 72.2%, 73.0% vs. 69.6%), but the diagnostic specificity of the CAD system was lower than that of junior physicians (62.1% vs. 66.9%). The diagnostic accuracy of the CAD system was lower than that of senior physicians (73.0% vs. 83.8%). However, the combination diagnosis of the CAD system with junior physicians had higher accuracy (81.8%) and AUC (0.842) than those of either the CAD system or junior physicians alone, and comparable diagnostic performance with those of senior physicians. The Kappa was 0.635 in the combination diagnosis of the CAD system with junior physicians, showing good consistency with the pathological results. The accuracy (76.4%) of the CAD system was the highest for nodules of 1-2 cm. CONCLUSION: The CAD system can effectively assist physicians to identify malignant and benign thyroid nodules, reduce the overdiagnosis and overtreatment of thyroid nodules, avoid unnecessary invasive fine needle aspiration, and improve the diagnostic accuracy of junior physicians.

Targeting Diagnosis of High-Risk Papillary Thyroid Carcinoma Using Ultrasound Contrast Agent With the BRAFV600E Mutation: An Experimental Study.

OBJECTIVE: High-risk papillary thyroid carcinoma (PTC) patients with BRAF mutation have lymph node and distant metastases and poor prognosis. Therefore, this study aims to develop a targeted ultrasound contrast agent for the BRAFV600E mutation to screen high-risk PTC at early stage. METHODS: The targeted lipid nanobubbles carrying BRAFV600E antibody were prepared using thin film hydration-sonication and avidin-biotin binding methods. The physicochemical properties and stability of the targeted nanobubbles were detected by transmission electron microscopy, atomic force microscopy, and confocal laser scanning microscopy. The target binding abilities of the targeted nanobubbles in the PTC cells (B-CPAP) overexpressed mutant BRAFV600E were evaluated by immunofluorescence staining, quantitative real-time polymerase chain reaction, western blot, and fluorescence microscopy. After PTC tumor models overexpressed mutant BRAFV600E were established, the enhanced images of targeted lipid nanobubbles and untargeted lipid nanobubbles on PTC tumors in nude mice were observed using contrast-enhanced ultrasound imaging. RESULTS: The targeted lipid nanobubbles revealed uniform, round morphology, and good stability with a nanoscale size. Besides, BRAFV600E monoclonal antibody was observed to be combined on the surface of lipid nanobubbles. Furthermore, the targeted nanobubbles had a good targeting diagnosis ability in PTC cells with BRAFV600E overexpression. Moreover, the targeted nanobubbles had better ultrasound enhancement and peak intensity of the time-intensity curve (P < .001) in PTC tumors with BRAFV600E overexpression as compared to the untargeted lipid nanobubbles. CONCLUSION: The targeted lipid nanobubbles carrying BRAFV600E antibody could be regarded as a potential targeted ultrasound contrast agent for the diagnosis of high-risk PTC.

Interobserver reproducibility of contrast-enhanced ultrasound in diabetic nephropathy.

OBJECTIVE: To investigate the interobserver reproducibility of contrast-enhanced ultrasound (CEUS) in patients with diabetic nephropathy. METHODS: A total of 40 patients with diabetic nephropathy were enrolled in this retrospective study. We measured peak intensity (PEAK), time-to-peak (TP), area under the curve (AUC) and mean transit time (MTT) of renal CEUS in each patient. Each parameter was performed by two independent observers. The interobserver reproducibility was assessed using intraclass correlation coefficients (ICCs) with 95% confidence intervals (CIs) and Bland-Altman plots by mean difference with 95% limits of agreement (LOAs). RESULTS: The parameters of the left and right kidneys showed moderate or good reliability. The best was the left kidney AUC parameters (ICC,0.945),with a 95% CI of 0.896-0.971.The Bland-Altman plots showed that the mean differences between the right renal parameters (PEAK, TP, AUC and MTT) obtained between the observers 1 and 2 were -6.63%,2.54%,-11.30%,-2.22%, and the 95% LOAs are -30.78 to 17.52%, -30.15 to 35.23%, -43.95 to 21.35%, -44.50 to 40.06%. While the left ones were -2.89%, 0.32%, -8.26%, 1.25% , and the 95% LOAs were -38.50 to 32.72%, -31.98 to 32.62%, -57.89 to 41.37%, -37.21 to 39.71%, respectively. CONCLUSION: Quantitative CEUS can show good interobserver reproducibility, which is better for the right kidney. It seems necessary to establish standardized techniques for obtaining contrast-enhanced quantitative analysis of renal blood perfusion. ADVANCES IN KNOWLEDGE: Quantitative assessment of renal perfusion by CEUS in patients with diabetic nephropathy provides diagnostic information. Furthermore, renal perfusion assessment in patients with diabetic nephropathy using CEUS has good reproducibility.

[Value of Contrast-enhanced Ultrasound Parameters in Evaluating K-W Nodule Formation in Diabetic Nephropathy].

Objective To discuss the value of contrast-enhanced ultrasound(CEUS)parameters in evaluating the formation of Kimmelstiel-Wilson(K-W)nodules in diabetic nephropathy(DN).Methods Sixty-two patients pathologically diagnosed with DN and undergoing CEUS in the First Medical Center of Chinese PLA General Hospital from March 2017 to January 2020 were assigned into two groups according to whether K-W nodules were formed.The cortical CEUS parameters and the ratios of cortical to medullary CEUS parameters were compared between the two groups.Results The 62 patients included 19 patients without K-W nodules(group A)and 43 patients with K-W nodules(group B).The median rise time(U=209,P=0.013)and fall time(U=197,P=0.007)in group B were significantly longer than those in group A.The median wash-in rate(WiR)(U=228,P=0.031)and wash-out rate(WoR)(U=229,P=0.032)in group B were significantly lower than those in group A.The median peak enhancement(PE)1/PE2(U=224,P=0.026),WiR1/WiR2(U=235,P=0.041),and WoR1/WoR2(U=230,P=0.043)ratios in group B were significantly lower than those in group A.The median FT1/FT2 ratio in group B was significantly higher than that in group A(U=227,P=0.038).Conclusion CEUS parameters can be used to quantitatively evaluate renal cortical microperfusion in DN patients with K-W nodules.

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.

Radiofrequency ablation versus total thyroidectomy in patients with papillary thyroid microcarcinoma located in the isthmus: a retrospective cohort study.

OBJECTIVE: This retrospective study aimed to examine the benefits and complications of radiofrequency ablation (RFA) in patients with papillary thyroid microcarcinoma (PTMC) in the isthmus. METHODS: This retrospective study included patients with PTMC in the isthmus and treated at the Chinese People's Liberation Army hospital from 05/2014 to 05/2018. The patients were divided into the RFA and total thyroidectomy (TT) groups. The outcomes were operation-related complications, rate of recurrence, metastasis rate, and thyroid carcinoma-specific questionnaire of quality of life (THYCA-QOL). RESULTS: Among 218 patients, 115 patients underwent RFA, and 103 underwent TT. The rates of disappearance of the ablation zone at 1, 3, 6, 12, and 18 months after RFA were 0.8% (1/115), 10.4% (12/115), 51.3% (59/115), 90.4% (104/115), and 100% (115/115), respectively. Surgical time, blood loss, hospital stays, and treatment costs were higher with TT than with RFA (all p < 0.001). The final THYCA-QOL score of the RFA group was significantly higher than in the TT group (p < 0.001). Minor pain at the operation site was seen in all patients in the RFA group. No distant metastasis was detected in all patients, but one patient in the RFA group had a recurrence after 6 months. The final THYCA-QOL score of the RFA group was significantly lower than in the TT group (p < 0.001). CONCLUSION: These results suggest that RFA for PTMC in the isthmus had similar outcomes than TT. It will have to be confirmed in future studies.

Evaluation of Renal Microperfusion in Diabetic Patients With Kidney Injury by Contrast-Enhanced Ultrasound.

OBJECTIVES: To conduct a quantitative analysis of renal microvascular perfusion in diabetic patients with kidney injury using contrast-enhanced ultrasound (CEUS). METHODS: A total of 172 patients with type 2 diabetes mellitus and kidney injury were recruited from May 2017 to November 2019. After collection of clinical characteristics, a CEUS examination was performed after injection of the contrast agent SonoVue (Bracco SpA, Milan, Italy). Time-intensity curves and renal perfusion parameters were analyzed. Ultrasound-guided renal biopsy was performed. The patients were divided into a diabetic nephropathy (DN) group and a nondiabetic renal disease (NDRD) group according to renal pathologic results. The discrimination of perfusion parameters between the groups was analyzed statistically with SPSS version 19.0 software (IBM Corporation, Armonk, NY). Receiver operating characteristic curves were used to illustrate the diagnostic performance of indicators. RESULTS: Ninety-eight patients, including 45 with DN (29 male; mean age ± SD, 57.76 ± 10.47 years) and 53 with NDRD (40 male; mean age, 48.7 ± 13.88 years) were included in this study. The peak enhancement (PE), wash-in the area under the curve (AUC), wash-in rate, wash-in perfusion index, wash-out AUC, wash-in and wash-out AUC, and wash-out rate were significantly different between the groups (P < .05). There were no differences in time-related parameters between the DN and NDRD groups (P > .05). The receiver operating characteristic curve analysis showed that the AUC for PE was 0.727, and PE lower than 7712.426 had diagnostic potential, with sensitivity of 81% and specificity of 40% in discriminating between NDRD and DN. CONCLUSIONS: The quantification of CEUS parameters can discriminate DN in diabetic patients with kidney injury. The PE and AUC may be feasible parameters.

Ultrasound-guided platelet-rich plasma injection and multimodality ultrasound examination of peripheral nerve crush injury.

Ultrasound-guided platelet-rich plasma (PRP) injection is able to make up for the limitations of applying a single growth factor. The goal of this study was to investigate the effects of serial ultrasound-guided PRP injections of the appropriate concentration on the treatment of sciatic nerve crush injury, and explore the value of multimodality ultrasound techniques in evaluating the prognosis of crushed peripheral nerve. In vitro, optimal concentration of PRP (from 150%, 250%, 450%, and 650%) was screened due for its maximal effect on proliferation and neurotrophic function of Schwann cells (SCs). In vivo, ninety rabbits were equally and randomly divided into normal control, model, PRP-2.5×, PRP-4.5×, and PRP-6.5× groups. The neurological function and electrophysiological recovery evaluation, and the comparison of the multimodality ultrasound evaluation with the histological results of sciatic nerve crush injury were performed to investigate the regenerative effects of PRP at different concentrations on the sciatic nerve crush injury. Our results showed that the PRP with a 4.5-fold concentration of whole blood platelets could significantly stimulate the proliferation and secretion of SCs and nerve repair. The changes in stiffness and blood perfusion were positively correlated with the collagen area percentage and VEGF expression in the injured nerve, respectively. Thus, serial ultrasound-guided PRP injections at an appropriate concentration accelerates the recovery of axonal function. Multimodality ultrasound techniques provide a clinical reference for prognosis by allowing the stiffness and microcirculation perfusion of crush-injured peripheral nerves to be quantitatively evaluated.

[Application of Ultrasound Model for Predicting Central Compartment Lymph Node Metastasis in Papillary Thyroid Carcinoma].

Objective To establish a predictive model for central compartment lymph node metastasis (CLNM) in patients with papillary thyroid carcinoma (PTC).Methods We retrospectively evaluated patients with histologically confirmed PTC treated in Chinese PLA General Hospital between January 2018 and January 2019.Totally 855 patients undergoing thyroidectomy with central lymph node dissection were enrolled in this study (577 in the training cohort and 278 in the validation cohort).The clinical manifestations of the patients and the ultrasound features of the tumors were recorded.To predict the probability of CLNM,we developed the clinical-ultrasound model with significant factors selected by the stepwise logistic regression.The Akaike Information Criterion (AIC) was use to select the optimal model,and the area under the curve (AUC) and the calibration curves were used to evaluate the performance of the prediction model.Results Multivariate analysis showed that sex (P<0.001),age 45-55 years (P=0.004) or ≥55 years (P=0.003),tumor size 1-2 cm (P<0.001) or >2 cm (P=0.008),multifocality (P=0.029),microcalcification (P=0.019),diffused distribution of microcalcifications (P=0.001),and vascularity levels 2-3 (P=0.002) were effective for CLNM prediction.The model based on the clinical and ultrasound features showed good performance in both training cohort with AUC of 0.78 (95%CI:0.74-0.82) and validation cohort with AUC of 0.70 (95%CI:0.67-0.76).Conclusions A quantitative model of CLNM in PTC patients was established based on the risk factors.According to the model,central lymph node dissection is recommended for PTC patients with high scores.

The Clinical Application of Core-Needle Biopsy after Radiofrequency Ablation for Low-risk Papillary Thyroid Microcarcinoma: A Large Cohort of 202 Patients Study.

Purpose: To evaluate the clinical application of core-needle biopsy (CNB) for low-risk papillary thyroid microcarcinoma (PTMC) after radiofrequency ablation (RFA) Methods: A total of 202 patients with 211 low-risk PTMCs were included in this study. RFA procedure was used the hydrodissection technique and moving-shot technique. Patients were followed at 1, 3, 6, 12 months and every 6 months thereafter. The volume of ablation area and the volume reduction ratio (VRR) were calculated. At 3 or 6 months after RFA, CNB was performed to the central zone, the peripheral zone and surrounding thyroid parenchyma for post-ablation evaluation. Results: The mean volume of tumors was 102.34±93.84 mm3 (range 4.19-424.10 mm3), which decreased significantly to 1.37±7.74 mm3 (range 0-73.30 mm3) at a mean follow-up time of 24.42±9.15 months (range 3-42 months) with a mean VRR of 99.14±4.18% (range 71.88-100%). A total of 3 ablation areas had positive CNB in the peripheral zone and underwent additional RFA. No recurrent or suspicious metastatic lymph nodes were detected Conclusion: CNB is a feasible and effective evaluation for low-risk PTMC after RFA, which can detect residual cancer cells early.

[Anhydrous Ethanol Improves Efficiency of Radiofrequency Ablation for the Treatment of Benign Thyroid Nodules:A Prospective Randomized Controlled Trial].

Objective To investigate the value of injecting a small amount of absolute ethanol into the benign solid nodules of the thyroid before radiofrequency ablation(RFA)to improve the efficiency of radiofrequency ablation. Methods A total of 98 eligible patients(98 nodules)with pathologically confirmed benign solid nodules who were treated in our center from December 2016 to February 2018 were included and randomized into ethanol ablation(EA)combined with radiofrequency ablation(RFA)group(EA+RFA group)and RFA group,with 49 patients in each group.Routine ultrasound,contrast-enhanced ultrasound(CEUS),and thyroid function test were performed before treatment and 1,3,6,and 12 months after treatment.The general information,treatment time,ablation energy,ablation power,postoperative nodule volume reduction ratio(VRR),symptom score(SS)and cosmetic score(CS),thyroid function level,and incidence of complications were compared between these two groups. Results The mean treatment time [(441.30±243.31)s vs.(790.70±349.82)s;t= 4.403, P=0.000],mean ablation energy [(3.92±2.01)kJ vs.(5.15±2.12)kJ;t=2.709, P=0.009],and mean ablation power [(6.07±1.44)W vs.(7.30±1.29)W;t=3.612, P=0.006] were significantly lower in the EA+RFA group than in the RFA group.At 3,6 and 12 months after surgery,the VRR in the EA+RFA group was(57.73±11.07)%(t=-3.16, P<0.001),(64.40±10.56)%(t=-5.45, P<0.001),and(77.29±8.48)%(t=-10.46, P<0.001),respectively;the VRR in the RFA group was(55.44±13.01)%(t=-1.76, P<0.001),(65.28±11.33)%(t=-5.09, P<0.001),and(75.17±9.84)%(t=-8.93, P<0.001),which were significantly smaller than those before surgery.There was no significant difference in VRR between the EA+RFA group and the RFA group at 1(t=3.41, P=0.33),3(t=2.05, P=0.21),6(t=2.77, P=0.49),and 12 months(t=5.05, P=0.10)after treatment.During the follow-up,no recurrence of nodules was observed on CEUS.In the EA+RFA group,the SS [(1.77±0.86)vs.(5.54±2.15);t=9.63, P<0.001] and the CS[(1.39±0.77)vs.(3.32±0.61);t=10.09, P=0.004]at 12 months after surgery were significantly lower than those before surgery.In the RFA group,SS [(1.63±1.04)vs.(5.90±1.79);t=12.72, P<0.001] and CS [(1.64±0.83)vs.(3.15±0.72);t=8.13, P=0.012] at 12 months after surgery were also significantly lower than those before surgery.The CSS in the EA+RFA group was significantly lower than that in the RFA group [(0.93±0.55)vs.(2.44±0.53);t=-11.70, P=0.007].Both groups had no significant change in thyroid function during the follow-up period,and no serious complications were observed. Conclusion Anhydrous alcohol injection can effectively improve the efficiency of radiofrequency ablation in treating benign solid thyroid nodules and is effective in reducing nodule volume,alleviating compressive symptoms,and decreasing cosmetic discomfort.

Potential value of three-dimensional ultrasonography in diagnosis of diabetic nephropathy in Chinese diabetic population with kidney injury.

BACKGROUND: To explore the potential value of three-dimensional ultrasonography (3DUS) and contrast-enhanced ultrasound (CEUS) in the diagnosis of diabetic nephropathy (DN) in Chinese diabetic patients with kidney injury. METHODS: Patients with type 2 diabetes mellitus and kidney injury in our hospital were enrolled, and the clinical characteristics as well as the laboratory data of patients were collected; 3DUS and CEUS were used to evaluate the morphological structure and blood perfusion of kidneys. Eligible patients were categorized into two groups based on renal biopsy results: DN group and non-diabetic renal diseases (NDRD) group. Correlation analysis and logistic regression analysis were applied to identify the risk factors of DN development. RESULTS: A total of 115 patients aged from 24 to 78 years old were recruited in the experiment, of which 64 patients (55.65%) and 51 patients (44.35%) were in the DN group and NDRD group, respectively. After correction to CKD stage, BMI and right kidney volume index were retained to identify patients with DN. The ROC of the logistic regression model had an AUC of 0.703 (95% CI: 0.591-0.815) and it was higher than both indicators. CONCLUSION: 3DUS has potential value in the diagnosis of diabetic nephropathy in Chinese diabetic population with kidney injury and may act as an auxiliary diagnosis for DN. More prospective and well-designed studies with larger samples are needed to verify the result.

Papillary thyroid carcinoma: an ultrasound-based nomogram improves the prediction of lymph node metastases in the central compartment.

OBJECTIVES: To develop a nomogram based on postoperative clinical and ultrasound findings to quantify the probability of central compartment lymph node metastases (CLNM). METHODS: A total of 952 patients with histologically confirmed papillary thyroid carcinoma (PTC) were included in this retrospective study and assigned to three groups based on sex and age. The strongest predictors for CLNM were selected according to ultrasound imaging features, and an ultrasound (US) signature was constructed. By incorporating clinical characteristics, a predictive model presented as a nomogram was developed, and its performance was assessed with respect to calibration, discrimination and clinical usefulness. RESULTS: Predictors contained in the nomogram included US signature, US-reported LN status and age. The US signature was constructed with tumour size and microcalcification. The nomogram showed excellent calibration in the training dataset, with an AUC of 0.826 (95% CI, 0.765-0.887) for male patients, 0.818 (95% CI, 0.746-0.890) for young females and 0.808 (95% CI, 0.757-0.859) for elder females. For male and young female patients, application of the nomogram to the validation cohort revealed good discrimination, with AUCs of 0.813 (95% CI, 0.722-0.904) and 0.814 (95% CI, 0.712-0.915), respectively. Conversely, for elderly female patients, the nomogram failed to show good performance with an AUC of 0.742 (95% CI, 0.661-0.823). CONCLUSION: This ultrasound-based nomogram may serve as a useful clinical tool to provide valuable information for treatment decisions, especially for male and younger female patients. KEY POINTS: • Age, gender, US-reported LN status and US signature were the strongest predictors of CLNM in PTC patients and informed the development of a predictive nomogram. • Microcalcification was the strongest predictor in the US signature, as CLMN was identified in approximately 92% of patients characterised by diffuse microcalcification. • Stratified by sex and age, this nomogram achieved good performance in predicting CLNM, especially in male and young female patients. This prediction tool may be useful as an imaging marker for identifying CLNM preoperatively in PTC patients and as a guide for personalised treatment.

[Quantitative Evaluation of Sciatic Nerve Crush Injury with Conventional Ultrasound Combined with Shear-wave Elastography in Rabbit Models].

Objective To explore the value of conventional ultrasound combined with shear-wave elastography in the quantitative evaluation of sciatic nerve crush injury in rabbit models. Methods Forty healthy male New Zealand white rabbits were randomly divided into four groups (n=10 in each group):three crush injury (CI) groups (2,4,and 8 weeks after crush) and control group (without injury). The thickness and stiffness of the crushed sciatic nerves and denervated triceps surae muscles were measured at different time points and compared with histopathologic parameters. Inter-reader variability was assessed with intraclass correlation coefficients. Results Compared with the control group,the inner diameters of the sciatic nerves significantly increased in the 2-week CI group [(1.65±0.34) mm vs. (0.97±0.15) mm,P=0.00] but recovered to the nearly normal level in the 8-week CI group [(1.12±0.18) mm vs. (0.97±0.15) mm,P=0.06];however,compared with control group [(8.75±1.02)kPa],the elastic modulus of the nerves increased significantly in all the CI groups [2-week:(14.77±2.53) kPa;4-week:(19.12±3.46) kPa;and 8-week:(28.39±5.26) kPa;all P=0.00];pathologically,massive hyperplasia of collagen fibers were found in the nerve tissues. The thickness of denervated triceps surae muscle decreased gradually,and the elastic modulus decreased 2 weeks after injury but increased gradually in the following 6 weeks;pathologically,massive hyperplasia of collagen fibers and adipocytes infiltration were visible,along with decreased muscle wet-weight ratio and muscle fiber cross-sectional area. The inter-reader agreements were good. Conclusion Conventional ultrasound combined with shear-wave elastography is feasible for the quantitative evaluation of the morphological and mechanical properties of crushed nerves and denervated muscles.

Solid benign thyroid nodules (>10 ml): a retrospective study on the efficacy and safety of sonographically guided ethanol ablation combined with radiofrequency ablation.

Background: Image-guided radiofrequency ablation (RFA) of large solid benign thyroid nodules (BTNs) usually require a high amount of energy. Injection of ethanol into a benign thyroid nodule before RFA can lower the procedural time and patient discomfort.Objective: To investigate the efficacy and safety of ethanol ablation (EA) combined with RFA in the treatment of solid BTNs (>10 ml) and to compare this modified method with RFA treatment alone.Methods: A total of 366 nodules in 366 patients were treated from June 2017 to Mar. 2018, 76 (M:F = 32:44, age 46 ± 14 years) were treated with EA + RFA and 290 (M:F = 99:191, age 49 ± 14 years) were treated with RFA. 44 patients (44 nodules) of each group formed a matched cohort after adjustment with propensity score matching. The average time, energy and power of the RFA procedure were retrospectively compared between the two groups. The postoperative nodule volume reduction ratio (VRR), compressive symptoms, cosmetic concerns, comprehensive satisfaction score, thyroid function and complications were retrospectively compared within and between the two groups after 6 months after treatment.Results: No significant differences were observed in the baseline characteristics between groups after propensity score matching adjustment. The mean RFA time (454.7 s (interquartile range (IQR), 290.8-589.0 s vs. 796.0 s (IQR, 554.0-976.30 s), p < .001), energy (3.69 ± 1.99 kJ vs. 5.10 ± 2.15 kJ, p = .009) and power (6.17 ± 1.38 W vs. 7.21 ± 1.29 W, p < .001) in the EA + RFA group were significantly lower than those in the RFA group. Mean nodule reduction at 6 months in the EA + RFA group and in the RFA group was 69.81 ± 11.48% vs. 67.43 ± 12.13% (10-30 ml, p = .454) and 62.75 ± 11.41% vs. 59.82 ± 10.53% (>30 ml, p = .456), respectively. The Medium nodules shrunk more than the large nodules (all p < .001), and the pressure symptoms and cosmetic signs significantly improved in the large nodules in both groups (all p < .05). Patients in the EA + RFA group had the highest satisfaction.Conclusions: EA combined with RFA shortened the ablation time of RFA, reduced the total energy and power required and improved patient satisfaction. This modified RFA approach may be considered a low-risk and high-efficacy alternative to treat solid BTNs greater than 10 ml in size.