1.Evaluation of placental oxygenation by blood oxygen level dependent MRI in hyperoxia
Ying PANG ; Ziyan SUN ; Qian LI ; Yuwei BAO ; Liming XIA
Chinese Journal of Radiology 2022;56(8):863-867
Objectives:To explore the value of blood oxygen level-dependent (BOLD) MRI in evaluating the changes of placental oxygenation during maternal hyperoxia.Methods:From October 2017 to March 2020, 22 singleton pregnant women with normal placenta showed by ultrasound were prospectively included in Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology. Pregnant women wore oxygen mask before examination, and then underwent BOLD MRI examination for 10 min. The pregnant women inhaled air in the first 3 min and continuously inhaled oxygen with purity greater than 90% in the next 7 min (flow rate 12 L/min). The average value of BOLD signal of the whole placenta, fetal side of placenta, maternal side of placenta and maternal kidney were measured and calculated in the first 3 min as before oxygen and the last 3 min of the end of oxygen inhalation as after oxygen. The ΔBOLD was calculated which was the change value of BOLD signal before and after oxygen inhalation. The BOLD values of placenta and maternal kidney before and after oxygen inhalation were compared by using paired t-test. The ΔBOLD of the whole placenta, the fetal side of the placenta and the maternal side of the placenta were compared by using one-way ANOVA, and the LSD method was used for pairwise comparison between groups. Results:There were significant differences in BOLD values of the whole placenta, fetal side of placenta and maternal side of placenta before and after oxygen inhalation ( t=-4.62, P<0.001; t=-4.73, P<0.001; t=-3.57, P=0.002). There was no significant difference in BOLD value of maternal kidney before and after oxygen inhalation ( t=0.35, P=0.740). The ΔBOLD values of the whole placenta, fetal side of placenta and maternal side of placenta were (12.8±2.2)%, (15.1±2.7)% and (6.4±1.3)% respectively. The overall difference was statistically significant ( F=4.49, P=0.015). The results of pairwise comparison showed that there was no significant difference in ΔBOLD between the whole placenta and the fetal side of the placenta ( P=0.450). There were significant differences in ΔBOLD between whole placenta and maternal side of placenta ( P=0.037) and between fetal side and maternal side of placenta ( P=0.005). Conclusion:Under the condition of maternal hyperoxia, the BOLD signal of placenta increased significantly, and the change of fetal side of placenta was more obvious than that of maternal side. BOLD-MRI has the potential of semi-quantitative and real-time evaluation of placental oxygenation.
2.Research progress in removal methods of electroencephalography artifacts evoked by transcranial magnetic stimulation
Ziyan PANG ; Wenshu MAI ; Jingna JIN ; Zhipeng LIU ; Tao YIN
International Journal of Biomedical Engineering 2023;46(6):569-574
Transcranial magnetic stimulation (TMS) combined with electroencephalography (EEG) is a non-invasive technique for studying the excitability and connectivity of the brain cortex, which has been applied in basic scientific research and clinical disease assessment. However, the applicability of TMS-EEG is limited due to artifacts of both biological and abiotic nature induced by TMS pulse output. To address this issue, in the past decade, researchers have developed various TMS-EEG artifact removal methods from two perspectives, including online experimental design and offline data post-processing, and have achieved numerous valuable results. In this paper, the currently available TMS-EEG artifact removal methods are reviewed to facilitate the application of TMS-EEG in basic research and clinical disease diagnosis and treatment.
3.Curative effect of Shuotong ureteroscopy combined with flexible ureteroscope in the treatment of 2-3 cm lower calyceal calculi
Yilong LIANG ; Ting DENG ; Shen CHEN ; Ziyan TANG ; Zhen LI ; Guoyou HE ; Jinsong PANG
International Journal of Surgery 2024;51(2):77-85
Objective:To investigate the efficacy of Shuotong ureteroscope combined with flexible ureteroscope in the treatment of 2-3 cm lower calyceal calculi, and analyze the influencing factors.Methods:A total of 102 patients with lower calyceal calculi were treated in the Second People′s Hospital of Yulin from February 2019 to December 2022, and they were divided into the observation group and the control group, with 51 cases in each group. The patients of the observation group were treated with Shuotong ureteroscope combined with flexible ureteroscope, while the patients of the control group were treated with flexible ureteroscope. According to whether the stones were completely removed after operation, all patients were divided into non-stone removal group ( n=13) and stone removal group ( n=89). The operation time, hospitalization time, lithotripsy time, intraoperative blood loss, complication rate and stone clearance rate were compared between the observation group and the control group. Generalized Estimation Equation was used to analyze and evaluate the effects of treatment time, treatment scheme and their interaction on visual analogue scale (VAS), white blood cell (WBC), blood urea nitrogen (BUN), blood creatinine (Cr), hemoglobin (HGB) and procalcitonin (PCT). Univariate and multivariate Logistic regression were used to analyze the risk factors of stone removal rate. Nomogram model was constructed based on risk factors and evaluate the model. Results:Compared with the control group, operation time [(118.72±9.61) min vs (136.65±11.27) min], hospitalization stay [(6.43±1.12) d vs (10.29±2.23) d] and the lithotripsy time [ (51.23±10.38) min vs (56.62±11.43) min] of the observation group were shorter, and the amount of intraoperative blood loss [(128.52±10.20) mL vs (157.53±15.31) mL] were significantly less than those of the control group ( P< 0.05). The results of Generalized Estimation Equation analysis showed that treatment time, treatment regimen and their interaction had significant effects on WBC, HGB, BUN, Cr, PCT and VAS ( P< 0.05). Compared with the control group, the incidence of complications (5.88% vs 19.61%) of the observation group was lower and the stone clearance rate ( 94.12% vs 80.39%) was significantly higher than those in the control group ( P< 0.05). The mode of operation, infundibulopelvic angle(IPA), caliceal pelvic height (CPH) and the maximum diameter of stones were all influencing factors of stone removal rate in patients with 2-3 cm lower calyceal calculi. The nomogram model constructed in this study has good differentiation, calibration and clinical practicability, and can better identify high-risk patients with incomplete removal of 2-3 cm lower calyceal calculi. Conclusions:Shuotong ureteroscope combined with flexible ureteroscope is a safe, effective method for the treatment of 2-3 cm lower calyceal calculi. It has the advantages of simple operation, less intraoperative bleeding, less postoperative complications and high stone clearance rate. IPA, CPH, the maximum diameter of calculi and the mode of operation were all independent factors affecting the stone clearance rate of 2-3 cm lower calyceal calculi. The nomogram model constructed in this study can well identify the high-risk patients with incomplete clearance of 2-3 cm lower calyceal calculi.