1.Dosimetry Study for Lung Metastases in SBRT Technology Using Tomo Planning System versus BrainLab Planning System
Jianwen HUANG ; Dehua KANG ; Senkui XU ; Wenbin ZHAO ; Shaoqing NIU ; Guoping SHEN ; Botian HUANG
Journal of Sun Yat-sen University(Medical Sciences) 2017;38(5):791-796
[Objective]To compare and contrast the dosimetry between Tomo planning and BrainLab planning for lung metasta-ses in stereotactic body radiation therapy(SBRT).[Methods]Four Patients with one,two,three and four metastases were selected. The PTV is 2.89 ± 1.15 cm3. Two plannings with total dose of 50 Gy to cover 95% of PTV ,5 Gy/Fraction and 10 fractions were designed using Tomo planning system and BrainLab planning system respectively. The DVH curves of spinal cord ,both lungs and normal tissue were compared. The conformity index andhomogeneityindex were analyzed as well.[Results]The homogeneity index (HI)and conformity index(CI)of the targets in Tomo planning system were 1.0314 ± 0.0700 and 0.687 ± 0.075,respectively. In BrainLab planning system the HI and CI of the targets were 1.0764 ± 0.1241 and 0.571 ± 0.042,respectively. To HI the P value in T test was less than 0.01 and the HI was better in Tomo than BrainLab and so was CI. The dose to spinal cord was higher in BrainLab planning system than that in Tomo. The dose to nomal tissue and both lungs were not different in the two planning systems and V20 of lung is as small as 10%.[Conclusions]For small volume lung metastases which longest diameter were less than 4 cm,the tomotherapy should be better choice.
2.Phase Ⅰ / Ⅱ clinical trial of docetaxel, cisplatin, and fluorouracil induction chemotherapy followed by intensity-modulated radiotherapy and concomitant chemotherapy in locally advanced nasopharyngeal carcinoma
Qun ZHANG ; Fang HE ; Dehua KANG ; Zhenyu WANG ; Bixiu WEN ; Wei LUO
Chinese Journal of Radiation Oncology 2013;(2):129-132
Objective To investigate the maximum-tolerated dose (MTD) of cisplatin in docetaxel,cisplatin,and fluorouracil (TPF) induction chemotherapy followed by intensity-modulated radiotherapy (IMRT) and concomitant chemotherapy as well as the safety and short-term efficacy of TPF induction chemotherapy in the treatment of locally advanced nasopharyngeal carcinoma (NPC).Methods Thirtythree patients with locally advanced NPC were enrolled in this trial.The MTD of cisplatin was determined by dose escalation study,and the short-term efficacy and toxicities were evaluated.Results When the doses of docetaxel and fluorouracil were 60 mg/m2 d1 and 550 mg/m2 d1-5,respectively,the MTD of cisplatin was 65 mg/m2 d1.In this regimen (repeated every 3 weeks),grade 3-4 toxicities included neutropenia (67%),febrile neutropenia (9%),diarrhea (21%),and oral mucositis (6%).Except those who experienced dose-limited toxicity,other patients completed the whole treatment schedule.After TPF induction chemotherapy,the overall response rate was 97%,and the complete response rate was 21%.Conclusions In the endemic areas of NPC,induction chemotherapy with docetaxel (60 mg/m2 d1),cisplatin (65 mg/m2 d1),and fluorouracil (550 mg/m2 d1-5),which is repeated every 3 weeks,is proved safe and effective for Asian patients with locally advanced NPC.
3.Study on the calibration for the outputs of photon and electron beams of dual-mode of linear accelerator based on IAEA 277 and 381 reports
Zhou JING ; Youfen CHEN ; Hang CHENG ; Jiabin CAI ; Lei ZHANG ; Dehua KANG
China Medical Equipment 2024;21(1):29-33
Objective:To calibrate the absorbed doses of the configured ray water with different gears of energies in accelerator based on
4.An imaging study on effect of total artificial disc replacement on lumbar sagittal alignment.
Wenzhi SUN ; Shibao LU ; Yong HAI ; Qingyi WANG ; Nan KANG ; Lei ZANG ; Yu WANG ; Tie LIU ; Dehua LIANG
Chinese Journal of Surgery 2016;54(2):104-107
OBJECTIVETo investigate effect of Activ L total lumbar disc replacement on lumbar sagittal alignment.
METHODSThe imaging data of patients with degenerative disc disease received Activ L total lumbar disc replacement at Department of Orthopedics, Beijing Chao-Yang Hospital, Capital Medical University from March 2009 to March 2013 were retrospectively analyzed. The average age was 45.6 years(range, 35-60 years)and the surgery levels were as follows: L3-4 2 cases, L4-5 15 cases, L5/S1 5 cases, L3-4+ L4-5 3 cases, L4-5+ L5/S1 7 cases. All patients were followed up for 15 to 63 months(average, 32 months). Radiographic parameters such as lumbar lordosis angle(LL), segment lordosis angle(SL) and sacral slope angle(SS) were recorded. All the radiographic parameters were compared using one-way ANOVA at different stage. Lumbar lordosis angle of the two-level was compared with the one of one-level by using independent sample t-test before and after the operation. A partial correction test was carried out to determine the corrections between the parameters preoperatively, one month after the operation and at final follow-up.
RESULTSOne month after the operation, the lumbar lordosis angle decreased by an average of 1.8°, but there was no statistically significant(P>0.05). Compared with one month postoperation, the lumbar lordosis angle increased by an average of 6.8°(P<0.05), which also increased a lot compared with preoperation(P<0.05). The value of segment lordosis angle was rising up from preoperation to the final follow-up(P<0.05), so was the value of sacral slope angle, but there was no statistically significant between different stage(P>0.05). The lumbar lordosis angle showed no significant difference between double-level ones and single-level ones at different stage(P<0.05). The lumbar lordosis angle showed positive correlation with the sacral slope(P<0.001), however, the lumbar lordosis angle showed no corrected with the segment angle all the time(P>0.05).
CONCLUSIONSThe total lumbar disc replacement with Activ L prosthesis had contributed to maintain and improve the lumbar alignment in the short and medium term. Double- or single-level total lumbar disc replacement had no significant effect on the value of lumbar lordosis angle. The lumbar lordosis angle showed positive correlation with the sacral slope all the time with no correlation between lumbar lordosis angle and sacral slope.
Diagnostic Imaging ; Humans ; Intervertebral Disc Degeneration ; surgery ; Lordosis ; diagnostic imaging ; Lumbar Vertebrae ; surgery ; Lumbosacral Region ; surgery ; Postoperative Period ; Prostheses and Implants ; Radiography ; Retrospective Studies ; Total Disc Replacement
5.Preliminary observation of new immobilization for total skin irradiation with helical tomotherapy
Senkui XU ; Wenyan YAO ; Jiang HU ; Yunfei XIA ; Dehua KANG ; Yalan TAO ; Xiaobo JIANG ; Jie LU ; Chengguang LIN
Chinese Journal of Radiation Oncology 2021;30(11):1183-1187
Objective:To preliminarily observe the feasibility of different immobilization techniques for total skin irradiation (TSI) using helical tomotherapy.Methods:Three eczema scrophuloderma patients treated with TSI in Sun Yat-sen University Cancer Center were immobilized with low-temperature thermoplastic in a prone position, diving suit combined with negative pressure vacuum bag in a supine position, low-temperature thermoplastic combined with vacuum bag in a supine position, respectively. Different immobilization effects were observed. The conformity index (CI) of the target area, heterogeneity index (HI) of the target area, and the mean dose (D mean) of the target area were calculated. Results:Three immobilization methods could achieve satisfactory immobilization effects, and all the dosimetric parameters of radiation treatment plans met the clinical requirements. The average set-up errors in the left and right, head and foot, and abdomen and back directions of three patients were (0.26±3.40) mm, (-2.63±4.63) mm and (6.13±4.86) mm, respectively. The CI, HI andD mean were0.56±0.09, 1.186±0.059 and (2586.56±63.28) cGy. Conclusions:Low-temperature thermoplastic or diving suits can be combined with vacuum bags for immobilization in TSI. The epidermal dose can be increased with bolus through the dose-building effect, which can provide a safe and reliable method for TSI in helical tomotherapy.