1.Physics issues on plan design and evaluation for stereotactic radiotherapy based on linear accelerator
Xuetao WANG ; Xin WANG ; Sen BAI ; Renming ZHONG
Chinese Journal of Radiation Oncology 2021;30(3):221-229
Stereotactic radiotherapy (SRT), also known as stereotactic ablative radiotherapy (SABR), includes stereotactic radiosurgery and stereotactic body radiotherapy (SBRT). This technique has the characteristics of large single fractional dose, few fractions, high equivalent biological doses, and rapid fall off-target doses. It can be implemented by relatively special equipment such as Gamma knife, Cyberknife, Tomotherapy and Vero 4D RT system, etc. In many cases, SBRT technique is employed based on linear accelerators. SRT differs from conventional radiotherapy in terms of the plan design and plan evaluation. Consequently, it is necessary to discuss the differences and provide guidance for clinical application and research.
2.Comparison of intravitreal injection of conbercept and macular photocoagulation for non-ischemic macular edema secondary to branch retinal vein occlusion
Guangfeng LIU ; Tingting HONG ; Sen MIAO ; Xin MENG ; Hua WANG ; Yusong JIA ; Xiuwen FU ; Jun WANG
Recent Advances in Ophthalmology 2017;37(7):658-661
Objectlve To assess the clinical effects and safety of intravitreal injection of conbercept and macular photocoagulation for non-ischemic macular edema secondary to branch retinal vein occlusion (BRVO).Methods A total of 50 patients (50 eyes) with non-ischemic macular edema following BRVO were retrospectively analyzed.Patients were divided into 2 groups:ICI group (26 eyes) received intravitreal injection of conbercept,laser group (24 eyes) received standard-of-care grid laser for macular edema.The best-corrected visual acuity (BCVA) and central macular thickness (CMT) were observed before and 1 week,1 month,2 months and 3 months after treatment.Then,the changes in pre-treatment and post-treatment were compared,and the related complications were recorded.Results The difference of BCVA before treatment was not significant between two groups (P > 0.05).BCVA at 1 week,1 month,2 months and 3 months after treatment in two groups were all improved,the differences were statistically significant compared with before treatment (all P < 0.05),and the differences were statistically significant between two groups after treatment (all P <0.05).At 3 months after treatment,BCVA of 18 patients (69.23%) in ICI group and 8 patients (33.33%) in ICI group improved 2 lines.The difference of CMT before treatment was not significant between two groups (P > 0.05),CMT at 1 week,1 month,2 months and 3 months after treatment in two groups were all decreased,the differences were statistically significant compared with before treatment (all P < 0.05),and the differences were statistically significant between two groups after treatment (all P <0.05).13 eyes received repeat intravitreal injection in ICI group,including 2 eyes at 1 month,7 eyes at 2 months with CMT >250 μm,and 3 eyes at 3 months.No severe side effect related with drug and intravitreal injection occurred in the two groups.Conclusion Mean BCVA change and CMT change are significantly greater in the intravitreal injection of conbercept than the standard-of-care grid laser group for the macuiar edema secondary to non-ischemic BRVO.
3.Clinical research on the therapeutic effects and safety of amitrine bismesylate in patients with mild vascular dementia
Jian-Ping JIA ; Xin WANG ; Sen-Yang LANG ; Zhong-Xin ZHAO ; Xiao-Ping PAN ; Li-Juan WANG ;
Chinese Journal of Neurology 2001;0(03):-
Objective To evaluate the therapeutic effects and safety of amitrine bismesylate in patients with mild vascular dementia.Methods An open multicenter self-controlled trial was carried out with 128 mild vascular dementia patients clinically diagnosed.Patients were treated with amitrine bismesylate in a dose of 2 tablets per day for 12 weeks.The neuro-psychologieal scale of MMSE,ADAS-cog,CDR, ADL were used to evaluate patients′cognitive condition before therapy and 6,12 weeks after treatment.The adverse effects,such as nausea and vertigo and so on,were monitored at the same time to evaluate the safety of this drug.Results After 3 months of treatment,the MMSE score(16.98 before therapy and 17.97 after treatment,P
4.Classification and reconstruction of 1 107 cases of maxillary defects
Sen YU ; Yang WANG ; Chi MAO ; Chuanbin GUO ; Guangyan YU ; Xin PENG
Journal of Peking University(Health Sciences) 2015;(3):509-513
Objective:To investigate the defect types and reconstruction methods of maxillary defects. Methods:The database of 1 107 cases with maxillary defects in Peking University School and Hospital of Stomatology from January 1985 to December 2010 was established. There construction methods were re-viewed. The defect types were classified according to Brown classification system. Results: In the 1 107 cases, 1 104 cases could be classified according to Brown classification system. The most common type was 2a with 559 cases (50. 6%). Among all the 1 107 cases, 349 cases were reconstructed with auto-transplantation, 443 cases with prosthesis, 107 cases untreated, and 208 patients lost to the follow-up. There was a significant growing trend over time for the application of free flaps and a downward trend of prosthesis. The most popular free flaps were fibular flap (88 cases) and radial forearm flap (75 cases) . Rectus abdominis flap and anterolatreal thigh flap were fit for extensive maxillary defects. Conclusion:The most common defect type is 2a. Free flap has become the dominant option for maxillary reconstruc-tion. Free flaps could be selected according to the maxillary defect types.
5.Analysis for surgical treatment of hepatolithiasis and the efficacy
Sen MA ; Rui WANG ; Huo-Xin LI ; Yue-Kui JIANG ; Fu-De BAO ;
Chinese Journal of Primary Medicine and Pharmacy 2006;0(12):-
Objective To study the relationship between the choice of operation and the efficacy on hepa- tolithiasis.Methods From Januray of 1995 to December of 2006,89 patients with hepatolithiasis underwent surgical treatment were retrospectively analyzed.Of them 33 cases underwent hepaticoplasty,hepatolobectomy in 7 cases, cholangiojejunostomy in 22 cases,choledocholithotomy with T-tube drainage in 27 cases.Results Out of the 89 cas- es,follow-up was completed in 81 cases for 6 months to 12 years.The postoperative stone residual rate of the group which underwent hepaticoplasty was 15.15 %(5/33)and cholannitis recurrence rate was 12.50 %(4/32),hepa- tolobecromy was 14.29%(1/7)and 16.67%(1/6),cholangiojejunostomy was 18.18%(4/22)and 30%(6/20), choledocholithotomy with T-tube drainage was 33.33 %(9/27)and 29.17 %(7/24).Conclusion Hepaticoplasty and hepatolobecromy were superior to cholangiojejunostomy and choledocholithotomy with T-tube drainage for treat- ment of hepatolithiasis.
6.Unveiling and Validating a Modified Method to Assess Cervical Sagittal Alignment as an Effective Substitute for Conventional C2-7 Cobb Angle
Wenpeng LI ; Qiwei WANG ; Qiancheng ZHAO ; Ziliang ZENG ; Xumin HU ; Xin LV ; Liangbin GAO
Clinics in Orthopedic Surgery 2025;17(1):130-137
Background:
Developing and validating a modified parameter, the SYS-G angle (the angle between the lower endplate of the C2 and the upper endplate of C7 vertebrae), as a feasible substitute for the C2–C7 Cobb method in assessing cervical sagittal alignment and exploring its reference range through a large-scale retrospective study.
Methods:
The visibility of the C6, C7 upper, and C7 lower endplates was graded and compared. Baseline data such as height, weight, body mass index (BMI), age, and sex were analyzed for their impact on the visibility of the C7 lower endplate. Values of C2-6 Cobb angle, SYS-G angle, and C2-7 Cobb angle were measured. The intra- and interobserver reliability, differences, and efficacy of evaluation on cervical lordosis of the parameters were compared, and the correlations among the parameters were analyzed. Furthermore, reference ranges for the SYS-G angle were established based on lateral cervical spine x-rays of 825 asymptomatic Chinese adults across different age groups and sexes.
Results:
The visibility of the C7 lower endplates was significantly reduced compared to the C6 lower and C7 upper endplates.Age, weight, BMI, and male sex were identified as factors negatively influencing the visibility of the C7 lower endplate. Both intraobserver and interobserver reliability demonstrated excellence for all tested parameters. The linear regression model unveiled a stronger association of the SYS-G angle with the C2-7 Cobb angle compared to the C2-6 Cobb angle. Furthermore, the SYS-G angle exhibited excellent efficacy in evaluating cervical lordosis. Age displayed a positive correlation with the SYS-G angle, and across every age bracket from 20 to 69 years, men exhibited a higher mean SYS-G angle compared to women.
Conclusions
The visibility of the C7 lower endplate diminishes with increasing age, weight, BMI, and male sex. In cases where the C7 lower endplate is unclear, the SYS-G angle emerges as a reliable method for estimating cervical sagittal morphology. Reference ranges for the SYS-G angle were established across various age groups and sexes among asymptomatic Chinese adults, offering a valuable resource to guide therapeutic interventions for cervical spine disorders and deformities.
7.Unveiling and Validating a Modified Method to Assess Cervical Sagittal Alignment as an Effective Substitute for Conventional C2-7 Cobb Angle
Wenpeng LI ; Qiwei WANG ; Qiancheng ZHAO ; Ziliang ZENG ; Xumin HU ; Xin LV ; Liangbin GAO
Clinics in Orthopedic Surgery 2025;17(1):130-137
Background:
Developing and validating a modified parameter, the SYS-G angle (the angle between the lower endplate of the C2 and the upper endplate of C7 vertebrae), as a feasible substitute for the C2–C7 Cobb method in assessing cervical sagittal alignment and exploring its reference range through a large-scale retrospective study.
Methods:
The visibility of the C6, C7 upper, and C7 lower endplates was graded and compared. Baseline data such as height, weight, body mass index (BMI), age, and sex were analyzed for their impact on the visibility of the C7 lower endplate. Values of C2-6 Cobb angle, SYS-G angle, and C2-7 Cobb angle were measured. The intra- and interobserver reliability, differences, and efficacy of evaluation on cervical lordosis of the parameters were compared, and the correlations among the parameters were analyzed. Furthermore, reference ranges for the SYS-G angle were established based on lateral cervical spine x-rays of 825 asymptomatic Chinese adults across different age groups and sexes.
Results:
The visibility of the C7 lower endplates was significantly reduced compared to the C6 lower and C7 upper endplates.Age, weight, BMI, and male sex were identified as factors negatively influencing the visibility of the C7 lower endplate. Both intraobserver and interobserver reliability demonstrated excellence for all tested parameters. The linear regression model unveiled a stronger association of the SYS-G angle with the C2-7 Cobb angle compared to the C2-6 Cobb angle. Furthermore, the SYS-G angle exhibited excellent efficacy in evaluating cervical lordosis. Age displayed a positive correlation with the SYS-G angle, and across every age bracket from 20 to 69 years, men exhibited a higher mean SYS-G angle compared to women.
Conclusions
The visibility of the C7 lower endplate diminishes with increasing age, weight, BMI, and male sex. In cases where the C7 lower endplate is unclear, the SYS-G angle emerges as a reliable method for estimating cervical sagittal morphology. Reference ranges for the SYS-G angle were established across various age groups and sexes among asymptomatic Chinese adults, offering a valuable resource to guide therapeutic interventions for cervical spine disorders and deformities.
8.Unveiling and Validating a Modified Method to Assess Cervical Sagittal Alignment as an Effective Substitute for Conventional C2-7 Cobb Angle
Wenpeng LI ; Qiwei WANG ; Qiancheng ZHAO ; Ziliang ZENG ; Xumin HU ; Xin LV ; Liangbin GAO
Clinics in Orthopedic Surgery 2025;17(1):130-137
Background:
Developing and validating a modified parameter, the SYS-G angle (the angle between the lower endplate of the C2 and the upper endplate of C7 vertebrae), as a feasible substitute for the C2–C7 Cobb method in assessing cervical sagittal alignment and exploring its reference range through a large-scale retrospective study.
Methods:
The visibility of the C6, C7 upper, and C7 lower endplates was graded and compared. Baseline data such as height, weight, body mass index (BMI), age, and sex were analyzed for their impact on the visibility of the C7 lower endplate. Values of C2-6 Cobb angle, SYS-G angle, and C2-7 Cobb angle were measured. The intra- and interobserver reliability, differences, and efficacy of evaluation on cervical lordosis of the parameters were compared, and the correlations among the parameters were analyzed. Furthermore, reference ranges for the SYS-G angle were established based on lateral cervical spine x-rays of 825 asymptomatic Chinese adults across different age groups and sexes.
Results:
The visibility of the C7 lower endplates was significantly reduced compared to the C6 lower and C7 upper endplates.Age, weight, BMI, and male sex were identified as factors negatively influencing the visibility of the C7 lower endplate. Both intraobserver and interobserver reliability demonstrated excellence for all tested parameters. The linear regression model unveiled a stronger association of the SYS-G angle with the C2-7 Cobb angle compared to the C2-6 Cobb angle. Furthermore, the SYS-G angle exhibited excellent efficacy in evaluating cervical lordosis. Age displayed a positive correlation with the SYS-G angle, and across every age bracket from 20 to 69 years, men exhibited a higher mean SYS-G angle compared to women.
Conclusions
The visibility of the C7 lower endplate diminishes with increasing age, weight, BMI, and male sex. In cases where the C7 lower endplate is unclear, the SYS-G angle emerges as a reliable method for estimating cervical sagittal morphology. Reference ranges for the SYS-G angle were established across various age groups and sexes among asymptomatic Chinese adults, offering a valuable resource to guide therapeutic interventions for cervical spine disorders and deformities.
9.Unveiling and Validating a Modified Method to Assess Cervical Sagittal Alignment as an Effective Substitute for Conventional C2-7 Cobb Angle
Wenpeng LI ; Qiwei WANG ; Qiancheng ZHAO ; Ziliang ZENG ; Xumin HU ; Xin LV ; Liangbin GAO
Clinics in Orthopedic Surgery 2025;17(1):130-137
Background:
Developing and validating a modified parameter, the SYS-G angle (the angle between the lower endplate of the C2 and the upper endplate of C7 vertebrae), as a feasible substitute for the C2–C7 Cobb method in assessing cervical sagittal alignment and exploring its reference range through a large-scale retrospective study.
Methods:
The visibility of the C6, C7 upper, and C7 lower endplates was graded and compared. Baseline data such as height, weight, body mass index (BMI), age, and sex were analyzed for their impact on the visibility of the C7 lower endplate. Values of C2-6 Cobb angle, SYS-G angle, and C2-7 Cobb angle were measured. The intra- and interobserver reliability, differences, and efficacy of evaluation on cervical lordosis of the parameters were compared, and the correlations among the parameters were analyzed. Furthermore, reference ranges for the SYS-G angle were established based on lateral cervical spine x-rays of 825 asymptomatic Chinese adults across different age groups and sexes.
Results:
The visibility of the C7 lower endplates was significantly reduced compared to the C6 lower and C7 upper endplates.Age, weight, BMI, and male sex were identified as factors negatively influencing the visibility of the C7 lower endplate. Both intraobserver and interobserver reliability demonstrated excellence for all tested parameters. The linear regression model unveiled a stronger association of the SYS-G angle with the C2-7 Cobb angle compared to the C2-6 Cobb angle. Furthermore, the SYS-G angle exhibited excellent efficacy in evaluating cervical lordosis. Age displayed a positive correlation with the SYS-G angle, and across every age bracket from 20 to 69 years, men exhibited a higher mean SYS-G angle compared to women.
Conclusions
The visibility of the C7 lower endplate diminishes with increasing age, weight, BMI, and male sex. In cases where the C7 lower endplate is unclear, the SYS-G angle emerges as a reliable method for estimating cervical sagittal morphology. Reference ranges for the SYS-G angle were established across various age groups and sexes among asymptomatic Chinese adults, offering a valuable resource to guide therapeutic interventions for cervical spine disorders and deformities.
10.Comparison of the failure mode of various types of glass ionomer cements.
Yan WANG ; Xin-chun ZHANG ; B W DARVELL
Chinese Journal of Stomatology 2006;41(11):687-689
OBJECTIVETo investigate the failure mode of various types of glass ionomer cements by Hertzian indentation test.
METHODSDiscs of 10 mm diameter and 2 mm thickness were prepared for six glass ionomer cement products (A-D: conventional type setting through an acid-base chemical reaction, A and B without reinforcement, C with silver reinforcement, D with ceramic reinforcement; E and F: resin-modified type), ten for each. These were tested on top of glass-reinforced polyamide-nylon 6, 6 substrates by a universal testing machine, loading centrally with a 20 mm diameter ball. Load at the first crack was recorded. Failure mode was observed under scanning electron microscope.
RESULTSThe former four products presented typical brittle fracture, while the latter two usually fractured incompletely. The failure loads at the first crack of the six glass ionomer cements were (258.86 +/- 10.49), (230.88 +/- 21.66), (281.90 +/- 25.39), (282.11 +/- 9.60), (756.67 +/- 83.50) and (1 148.00 +/- 147.78) N, respectively. Significant difference was found between the former four and the latter two products.
CONCLUSIONSThe type (setting mode) of glass ionomer cement controls its failure mode. Inclusion of metallic or ceramic filler has little effect on increasing the load bearing capacity of glass ionomer cement.
Compressive Strength ; Dental Porcelain ; chemistry ; Glass Ionomer Cements ; chemistry ; Materials Testing ; methods ; Resins, Synthetic ; chemistry ; Silver ; chemistry