Objective To investigate the most appropriate low radiation dose in multi-slice CT (MSCT) scans for orbital trauma patients. Methods Thirty trauma patients with suspected orbital fractures who underwent helical CT scans with a 64-MSCT using regular dose were selected. Noise was artificially introduced to the axial images using an image space noise addition tool to simulate 6 sets of lower dose scans with tube current of 30, 70, 100, 140, 170 and 200 mA, respectively. The lowest tube current with adequate image quality for confident diagnosis was determined based on the evaluation of the overall image quality and fracture detection on images at different dose levels. The determined lowest tube current was then validated using clinical scans. Radiation dose related parameters CTDIvol, DLP, ED were also recorded.Image quality was evaluated according to its low-density resolution, noise and structure clarity and characterized into 5-grades of excellent, good, fair, worse and worst Rank sum test and X2 test were wsed for statistics. Results In 30 trauma patients with regular dose of 300 mA, there were 30 cases of orbital fracture, 19 cases of intraorbital emphysema, 12 cases of ocular muscle injury and 1 case of intraorbital foreign body. These changes could still be clearly observed and correctly diagnosed when the tube current was reduced to as low as 70 mA. However, the overall image quality was mostly fair. At the simulated dose of 100 mA, the majority of images were characterized as excellent or good, and there was no statistical difference compared with that of regular dose scans (P > 0.05 ) . In the clinical evaluation for 20 orbital trauma patients with the reduced tube current of 100 mA, the majority of images were judged to be excellent (9 cases) or good(17 cases) and fair (4 cases). The radiation dose(0. 29 mSv) was reduced by 70% compared with that of regular tube current of 300 mA(0. 86 mSv). Conclusion The tube current of MSCT may be used as low as 100 mA in orbital trauma patients to reduce radiation dose and keep the image quality diagnosable.

Objective:To investigate the prognostic value of serum levels of miR-134 and miR-146b in elderly patients with acute ischemic stroke(AIS).Methods:A total of 162 elderly patients with AIS admitted to the Third People's Hospital of Haikou from January 2017 to October 2019 were enrolled.According to modified Rankin Scale(mRS)scores, they were divided into the good prognosis group(n=98, mRS score≤2)and the poor prognosis group(n=64, mRS score>2). Based on the National Institutes of Health Stroke Scale(NIHSS), patients were divide into the mild group(n=46, NIHSS score<5), moderate group(n=75, 5≤NIHSS score≤20), and severe group(n=41, NIHSS score>20). Real-time fluorescence quantitative PCR was used to detect serum levels of miR-134 and miR-146b in each group.Multivariate logistic regression was used to analyze risk factors for poor prognosis in elderly patients with AIS.The receiver operating characteristic(ROC)curve was used to analyze the value of serum miR-134 and miR-146b levels in predicting poor prognosis of elderly patients with AIS.Pearson correlation was used to analyze the correlations of serum levels of miR-134 and miR-146b with NIHSS and mRS scores in elderly patients with AIS.Results:Serum levels of miR-134(3.26±1.13 vs.0.85±0.38)and miR-146b(2.27±0.93 vs.0.56±0.21)were higher in the AIS group than in the control group( t=14.360 and 12.527, P<0.01). Serum levels of miR-134(4.35±1.46 vs.2.28±0.85)and miR-146b(3.07±1.04 vs.1.51±0.66)were higher in the poor prognosis group than in the good prognosis group( t=13.520 and 11.242, P<0.01). Serum levels of miR-134 and miR-146b in the severe group were higher than in the moderate and mild groups( t=10.815 and 9.462, P<0.01), and they were also higher in the moderate group than in the mild group( t=13.627, 11.611, P<0.01). Multivariate Logistic regression analysis showed that serum miR-134( OR=2.470, 95% CI: 1.603-4.927)and miR-146b( OR=1.914, 95% CI: 1.350-3.406)were risk factors for poor prognosis in elderly AIS patients( P<0.05). The ROC curve analysis showed that the optimal cut-off values of serum miR-134 and miR-146b to predict poor prognosis in elderly AIS patients were 3.84 and 2.68, respectively.The area under the ROC curve(AUC)of combined serum miR-134 and miR-146b(0.926, 95% CI: 0.865-0.987)for the prediction of poor prognosis was higher than that of either marker alone, with a sensitivity and specificity of 92.4% and 86.2%, respectively.The correlation analysis showed that serum levels of miR-134 and miR-146b were positively correlated with NIHSS and mRS scores in elderly AIS patients( r=0.806, 0.871, 0.785 and 0.842, all P<0.01). Conclusions:Increased serum miR-134 and miR-146b levels are correlated with the severity of neurological impairment and prognosis in elderly patients with AIS.Serum miR-134 and miR-146b levels together have a high value in predicting poor prognosis in elderly AIS patients.

Objective: To explore the effectiveness and safety of ultrasound-guided radiofrequency ablation (RFA) in treatment of thyroid benign nodules. Methods: We analyze 573 patients with thyroid benign nodules from June 2014 to September 2017 treated by RFA at Department Ⅱof Thyroid Surgery, the First Affiliated Hospital of Zhengzhou University. Among these patients, there were 75 males and 498 females, with a median age of 45 years old. All patients were diagnosed as thyroid benign nodules by ultrasound-guided fine needle aspiration biopsy before RFA. A total of 750 benign tumors were treated. To evaluate the thyroid function of the patients before RFA and 3 months after it, and to observe the changes of thyroid benign nodules by ultrasound at 3, 6, 12 months after RFA. The paired t-test was used to compare the measurement data with normal distribution, and Wilcoxon's signed rank test was used to compare the measurement data with non-normal distribution. To calculate the volume change and reduction rate of thyroid benign nodules. Results: RFA was successfully completed in all patients, the volume reduction rate was 67%(48%, 83%) in the 3rd month after RFA, in the 6th month was 81%(67%, 91%), in the 12th month was 89%(80%, 95%). Eighteen patients felt pain during RFA, but the pain was alleviated after stopping ablation. Three patients′ tone decreased, but recovered in a week. Hoarseness occurred in 6 patients and recovered in 3 months. Three patients had neck hemorrhage, which was managed with simple compression of the neck. Conclusions RFA is an effective and safe treatment for thyroid benign nodules and has obvious advantages such as less invasiveness, having no influence in thyroid functions. It is clinically prospective for application.