Objective:To investigate the value of CT enhancement degree in diagnosing cervical lymph node metastasis of papillary thyroid carcinoma (PTC) .Methods:CT data of 535 neck lymph nodes with pathological diagnosis in 251 cases were retrospectively analyzed. The ratio and difference between the density of CT enhancement and plain scan were calculated. Mann-Whitney test was used to analyze the distribution of ratio and difference in lymph node metastasis group and non-metastasis group. The optimal thresholds of ratio and difference in the two groups were obtained by receiver operating characteristic (ROC) curve analysis.Results:535 cervical lymph nodes including 271 in metastatic group and 264 in non-metastatic group. The ratios of two groups were 2.30 (2.04, 2.76) and 1.66 (1.51, 1.81) ( Z=-16.94, P<0.05) respectively, and the differences were 58 (49, 76) Hu and 31 (22, 36) Hu ( Z=-18.045, P<0.05) respectively. When the ROC area under curve of ratio and difference between the two groups were 0.923 and 0.951 respectively, the optimal thresholds were 1.93 and 39.5Hu respectively. The sensitivity and specificity of diagnosing lymph node metastasis were 84.9% and 87.1%、91.5% and 86.0%respectively.The sensitivity and specificity of combination of the two diagnosing lymph node metastasis were 82.3% and 91.7%. Conclusions:The ratio of enhancement and plain scan density ≥1.93 and the difference ≥39.5Hu have a high diagnostic efficiency for cervical lymph node metastasis of PTC. The specificity of the two is similar, but the latter has higher sensitivity. The combination of the two can significantly improve the specificity, thereby reducing unnecessary surgical trauma.

OBJECTIVE To analyze the relationship between LPR and common pharyngeal diseases and its risk factors.METHODS A total of 280 patients who were admitted to the Inpatient Department of Otolaryngology Head and Neck Surgery or Laryngoscopy Room of the First Affiliated Hospital of Harbin Medical University due to throat discomfort from September 2022 to May 2023 were selected as the study objects.All enrolled patients were required to complete the RSI and RFS scoring scales.According to the 2022 LPRD expert Consensus,RSI>13 and/or RFS>7 were classified as LPR group,and RSI≤13 and RFS≤7 are classified as non-LPR group.Chi-square test was used to analyze the differences in the incidence of common pharyngeal diseases such as upper respiratory tract papilloma,epiglottic cyst,vocal cord polyp,vocal cord leucoplakia,vocal cord cancer and hypopharyngeal cancer among different groups.Univariate Chi-square test analysis and multivariate binary logistic regression analysis were performed for gender,age,BMI,smoking and drinking history.All differences were statistically significant with P<0.05.RESULTS The prevalence of LPR in 280 patients with throat discomfort was 70.0%(196/280).There were statistically significant differences in the incidence of LPR group and non-LPR group in patients with vocal cord polyp(χ2=4.228,P<0.05),vocal cord leukoplakia(χ2=12.283,P<0.05),vocal cord cancer(χ2=4.103,P<0.05)and hypopharyngeal cancer(χ2=4.907,P<0.05),while there was no significant difference in the incidence of LPR group and non-LPR group in patients with papilloma of upper respiratory tract(χ2=0.183,P>0.05)and epiglottic cyst(χ2=0.556,P>0.05).Univariate analysis showed that there were significant differences in the incidence rates of smoking(χ2=20.403,P<0.05)and drinking(χ2=7.704,P<0.05)between the LPR group and the non-LPR group,while gender(χ2=0.01,P>0.05),age(χ2=8.147,P>0.05),BMI(χ2=2.060,P>0.05)had no significant difference.Multivariate logistic regression analysis showed that smoking(OR=3.390,95%CI:1.761-6.526,P<0.05)was an independent risk factor for LPR.CONCLUSION There is a high co-prevalence of LPR with vocal cord polyps,vocal cord leukoplakia,vocal cord cancer and hypopharyngeal cancer.Therefore,LPR should be evaluated when treating throat related diseases,and LPR should be actively treated if necessary.In addition,smoking and drinking are risk factors for LPR,so it is necessary to stop smoking and drinking alcohol when treating LPR.

Objective On the basis of explicit dynamics calculation theory, a numerical model for calculating active and passive properties of muscles with high strain rate was proposed. Methods In the process of calculating the motion equation of muscle element with high strain rate, Hill’s three-factor muscle model with high strain rate was introduced into the noda force formula to modify the node force in each time step. Results As Hill’s three-factor muscle model was introduced in numerical calculation, the muscle element had the passive characteristics of the general structural constitutive model and its proprietary active characteristics. Conclusions The research findings will contribute to numerical calculation for dynamic response and damage of muscles with high strain rate.

Objective:To study the application value of narrow-band imaging in the diagnosis of laryngopharyngeal reflux. Methods:A total of 275 patients admitted to the inpatient department or laryngoscopy room of the Otolaryngology Head and Neck Surgery Department of the First Affiliated Hospital of Harbin Medical University from September 2022 to April 2023 due to throat discomfort were selected as the research subjects. All of them completed RSI, RFS scoring scales and electronic laryngoscopy（including ordinary white light and NBI）. According to the expert consensus of LPRD in 2022, RSI and RFS scoring scale were used as diagnostic criteria to divide them into LPR group and non-LPR group. Chi-square test was used to analyze the differences of positive rates of characteristic manifestations under NBI among different groups. The consistency of NBI and scale diagnostic methods was analyzed by Kappa, and RSI and RFS scoring were used as diagnostic criteria, The diagnostic efficiency of NBI method was analyzed. Results:There were 190 people in the LPR group, 157 of whom showed characteristic performance under the NBI mode, with a positive rate of 82.6%（157/190）; there were 85 people in the non-LPR group, with a positive rate of 18.8%（16/85）. There was a statistically significant difference in the positive rate between the two groups（χ²=102.47, P<0.05）. The consistency rate between RSI, RFS and NBI was 82.2%（226/275）. Kappa consistency analysis was used, and Kappa=0.605（P<0.05）, indicating good consistency between the two diagnostic methods. Using RSI and RFS as diagnostic criteria for LPR, the sensitivity of NBI diagnostic method was 82.6%（157/190）, specificity 81.2%（69/85）, positive predictive value 90.8%（157/173） and negative predictive value 67.6%（69/102）. Conclusion:Narrow-band imaging, as a new endoscopic imaging technique, can show small changes in mucosal surface micro vessels and play an important role in the diagnosis of laryngopharyngeal reflux.
Humans ; Laryngopharyngeal Reflux/diagnostic imaging* ; Narrow Band Imaging ; Laryngoscopy/methods* ; Pharynx ; Predictive Value of Tests