1.Effects of different doses of dexmedetomidine on cerebral oxygen saturation and pulmonary shunt fraction in patients undergoing one-lung ventilation
Yun MENG ; Hua ZHANG ; Zhiqun XIA ; Yonghao YU ; Chunhua SONG
Tianjin Medical Journal 2016;44(5):602-604
Objective To investigate the effects of different doses of dexmedetomidine on cerebral oxygen saturation and pulmonary shunt fraction in patients undergoing one-lung ventilation (OLV). Methods Sixty ASAⅠ-Ⅱpatients, aged 46-71 years, with body mass index (BMI)18-24 kg/m2 and scheduled for thoracotomy were randomly divided into three groups (n=20 each):high dose dexmedetomidine group (group D1), low dose dexmedetomidine group (group D2) and control group (group C). Dexmedetomidine 1μg/kg was infused in group D1 after anesthesia induction, and then a rate of 0.5μg·kg-1·h-1 was continuously infused. Dexmedetomidine 0.5μg/kg was infused in group D2 after anesthesia induction, and then a rate of 0.3μg · kg-1 · h-1 was continuously infused. Group C was received the equal volume of normal saline. Anesthesia was main?tained with propofol-remifentanil and intermittent iv boluses of rocuronium. Arterial and jugular venous blood samples were collected before anesthesia induction (T0), at 15 min after two-lung ventilation (T1), at 5 min (T2) and 30 min (T3) of OLV for blood gas analysis. Value of Qs/Qt was calculated and SctO2 was recorded at the same time. Results Compared with group C and group D2, Qs/Qt was decreased at T2 in group D1 (P<0.05). Qs/Qt was lower at T3 in group D1 and D2 than that of group C, and which was lower in group D1 than that of group D2 (P<0.05). In group C and group D1 a significant de?crease in SctO2 was observed at T2 and T3 compared to that at T0 and T1 (P<0.05). SctO2 was significantly higher at T2 and T3 in group D2 than that in group C and group D1 (P<0.05). Conclusion Dexmedetomidine given during OLV undergoing thoracotomy can improve oxygenation, decrease pulmonary shunt fraction and reduce the occurrence of low SctO2.
2.Analysis of malaria epidemiological characteristics in Hechi City,Guangxi Zhuang Autonomous Region from 2005 to 2015
Zhiqun MENG ; Jiangrong HUANG ; Shaoyi HUANG ; Guangteng LONG ; Kangming LIN ; Yaming HUANG
Chinese Journal of Schistosomiasis Control 2017;29(1):83-86
Objective To analyze the epidemiological characteristics of malaria in Hechi City,Guangxi Zhuang Autono?mous Region from 2005 to 2015,so as to provide the evidence for formulating and adjusting measures of malaria elimination. Methods The data of malaria cases in 11 counties of Hechi City from 2005 to 2015 were collected and analyzed by using Micro?soft Office Excel 2003 and SPSS 17.0. Results A total of 160 malaria cases were reported in Hechi City from 2005 to 2015, and the annual average malaria incidence was 3.6 per million. There were 10 local recurrence cases(accounting for 6.25%,10/160)and 150 imported cases(accounting for 93.75%,150/160). For the etiology,Plasmodium vivax accounted for 51.87%(83/160)in these cases,P. falciparum accounted for 34.38%(55/160),P. ovale accounted for 1.25%(2/160),P. malariae account?ed for 5.00%(8/160),and the indeterminate accounted for 7.50%(12/160). During the period of 11 years,the malaria inci?dence first dropped and then rose. There were no local cases after 2009. However,an imported falciparum malaria death case was reported in 2010,a severe imported falciparum malaria case was reported in 2013 and another in 2015. A severe case of ma?ternal?neonatal vivax malaria was reported in 2014. These cases were mainly distributed in 10 counties of Hechi City,with more young male adults who engaged in digging mining. More cases concentrated from April to August. Most of the reported malaria cases were imported,60.00%(96/160)of them returned from Africa and Southeast Asia,and 33.75%(54/160)from other do?mestic provinces. The median of the interval from symptom appearance to diagnosis was 5 d,and there was a significant differ?ence among the above years(c2=33.40,P<0.05). Conclusions Malaria is still an important public health problem in Hechi City,and the appropriate control measures and effective tools should be strengthened for malaria elimination. The key to consoli?date the achievements of malaria control is strengthening the malaria monitoring management of the floating population.
3.The application of the RapidPlan module based on O-ring accelerator in volumetric modulated arc therapy for cervical cancer
Zhen ZHOU ; Bo YANG ; Zhiqun WANG ; Heling ZHU ; Xiangyin MENG ; Tingting DONG ; Jie QIU
Chinese Journal of Radiological Medicine and Protection 2022;42(9):691-696
Objective:To study the clinical feasibility and advantages of the RapidPlan module based on Halcyon 2.0 ring medical linear accelerator in the design of volumetric modulated arc therapy (VMAT) plans after cervical cancer surgery.Methods:The data of 98 clinical cervical cancer cases were selected from the database, and VMAT artificial radiotherapy plans were designed based on Halcyon 2.0. Then, the designed plans were imported into the RapidPlan module to train the module for a prediction model with high goodness of fit. Another 20 patients after cervical cancer surgery were selected as the validation set to compare the differences in dosimetry, plan consistency, and plan execution efficiency between the manual plans and RapidPlan automatic plans.Results:The RapidPlan automatic plans could obtain dose distribution of target volume and organs at risk with the same quality as the manual plans. The RapidPlan automatic plans provided slightly inferior protection of the femoral head but superior protection of the spinal cord compared to the manual plans, and the difference was statistically significant ( t = 4.71, P<0.001). The average MU of the RapidPlan automatic plans was 687.46, which was lower than that of the manual plan (815.34), and the difference was statistically significant ( t = 6.09, P < 0.05). The portal dosimetry (PD) verification revealed that the average γ passing rate (1 mm/1%) of the RapidPlan automatic plans was 89.48%and that of the manual plans was 88.22%, and the difference was statistically significant ( t = 3.35, P < 0.05). Conclusion:RapidPlan automatic plans based on the Halcyon 2.0 platform can meet the clinical needs of the VMAT program for cervical cancer and has certain advantages.
4.Research on the robustness of Ethos cervical cancer online fully automatic generation of adaptive plans
Bo YANG ; Zhiqun WANG ; Xiangyin MENG ; Yongguang LIANG ; Tingtian PANG ; Xingliu WANG ; Xiaoshen WANG ; Hongying LUO ; Jiawei CHEN ; Fuqiang CHEN ; Zongkai ZHOU ; Zhen ZHANG ; Jie QIU
Chinese Journal of Radiation Oncology 2024;33(2):145-151
Objective:To evaluate the robustness of fully automated adaptive planning for Ethos online adaptive radiotherapy (ART) based on the intelligent optimization engine (IOE).Methods:Clinical data of 11 stage ⅠB cervical cancer patients admitted to Peking Union Medical College Hospital between June 2021 and June 2022 were retrospectively analyzed. Original planning images and iterative cone-beam computed tomography (iCBCT) images of each radiotherapy treatment were acquired, and all patient data were imported into the Ethos simulator. IOE-based 9-field automatic plan generation was performed for 11 patients using Ethos, and the generated plans were sent to online adaptive radiotherapy simulation to obtain each online adaptive radiotherapy plan (273 fractions in total) and complete the simulated treatment. For comparison, manual plan design was performed based on the images and contoured structures used for online adaptive radiotherapy planning, and the manually plans created with evenly divided 9 fields. Dosimetric parameters, plan complexity parameters, and Mobius quality assurance (QA) pass rates were collected to compare and evaluate the robustness of the online adaptive radiotherapy plan in terms of organs at risk (OAR), target volume dosimetric parameters, and plan complexity by using paired t-test or rank sum test. Results:The online adaptive plan of cervical cancer had comparable planning target volume (PTV) coverage compared to the manual plan. For the clinical target volume (CTV) D 99%, online adaptive plan was significantly higher than the manual plan [(45.93±0.36) vs. (45.32±0.31) Gy, P<0.001]. For hot dose area, the maximum point dose (PTV D max) of adaptive plan was significantly higher than the manual plan [(49.89±1.25) vs. (48.48±0.77) Gy, P<0.001], but the PTV D 1% of adaptive plan was significantly lower than the manual plan [(47.22±0.29) vs. (47.59±0.48) Gy, P<0.001]. There was no statistical difference in the conformal index ( P=0.967). And there was significant difference in the homogeneity index, with same medians and less dispersion in adaptive plan ( P<0.001). For OAR dose, bladder D mean, rectal V 40 Gy, small intestine D mean of adaptive plan was slightly higher than that of the manual plan; the rectal D mean, small intestine D 2 cm3 of the adaptive plan was slightly lower than that of manual plan; dosimetric parameters of right and left femoral heads, spinal cord and bone marrow of the adaptive plan were better than those of manual plan. The adaptive plan had more monitor units (MU) than the manual plan, but the complexity of the adaptive plan was significantly lower than that of the manual plan (0.135±0.012 vs. 0.151±0.015, P<0.001). For Mobius γ pass rate (5%/3 mm), both adaptive and manual plans met clinical requirements. Conclusion:Ethos cervical cancer online adaptive plan, which is based on the IOE engine, demonstrates good robustness and ensures the quality of online adaptive plans generated for each treatment fraction.
5.Performance evaluation of Ethos intelligent optimization engine in automatic plan generation
Zhiqun WANG ; Bo YANG ; Xiangyin MENG ; Yongguang LIANG ; Tingtian PANG ; Xingliu WANG ; Xiaoshen WANG ; Hongying LUO ; Jiawei CHEN ; Fuqiang CHEN ; Zongkai ZHOU ; Zhen ZHANG ; Jie QIU
Chinese Journal of Radiation Oncology 2024;33(4):339-345
Objective:To evaluate the automatic optimization performance and clinical feasibility of the intelligent optimization engine (IOE) in the Ethos online adaptive radiotherapy platform.Methods:Clinical data of 11 patients with postoperative cervical cancer treated with Halcyon accelerator were retrospectively analyzed. Manual planning was performed for all patients using the 4 full arc volumetric modulated arc therapy (VMAT) (Manual-4Arc) in Eclipse, with a prescription dose of 45 Gy/25F. Patient images and structures were imported into the Ethos simulator, and appropriate clinical goals were added based on clinical requirements. The target coverage was normalized to 95%. Automatic plan generation was conducted using IOE, resulting in 7, 9, and 12 field intensity modulated radiotherapy (IMRT) plans (IMRT-7F、IMRT-9F、IMRT-12F), as well as 2 and 3 arc VMAT plans (VMAT-2Arc、VMAT-3Arc). Dosimetric index comparisons were made between the Manual-4Arc plans and the 5 groups of IOE-generated plans through one-way analysis of variance. Based on the analysis results, Turky post hoc multiple comparisons were performed to evaluate the automatic optimization performance of IOE.Results:In terms of the high dose area, the IMRT-12F plans showed the lowest D 1% for the planning target volume (PTV), and there were significant differences compared to the Manual-4Arc plans ( P=0.004). Regarding target coverage, all groups produced clinical target volume (CTV) plans that met the clinical requirements. Although the Ethos online adaptive plans were normalized during planning, the PTV coverage was slightly insufficient. For organs at risk (OAR) close to the target, such as the bladder, there were significant differences in V 30 Gy, V 40 Gy, and D mean among the 6 groups of plans. The dose ranking for the bladder was generally as follows: IMRT-12F