摘要
目的:研究驻留时间离差限制(DTDC)参数对三维后装计划的影响。方法:选取在中国医科大学附属第一医院治疗的30例妇科肿瘤患者计划,施源器为Fletcher单独宫腔管、全部三管和阴道施源器,每例患者治疗前扫描CT,并由医生勾画靶区和危及器官,以0.1步进修改DTDC参数,由DTDC=0到DTDC=1共制定11个计划,归一至DTDC=0时计划下相应的数值。比较CTV的V_(150)、V_(200),膀胱、直肠的D2cc,驻留时间总和,计划调制指数,分析DTDC参数的修改对三维后装计划的影响。结果:随着DTDC的增加,阴道施源器,Fletcher施源器单独宫腔管和全部三管使用时,CTV的V_(150)和V_(200)分别升高至105%和109%、102%和104%以及115%和120%,直肠和膀胱的D2cc分别至101%和102%、99%和99%以及115%和101%;总驻留时间分别达到DTDC=0时的96%、97%和104%。结论:宫颈癌三维后装计划的制定针对不同的施源器应该选用合适的DTDC参数,给予患者更加合理治疗计划。
Objective To study the effects of dwell time deviation constraint（DTDC） parameters on three-dimensional（3 D）afterloading plan. Methods Fifteen patients with gynecologic tumors who were treated in the First Hospital of China Medical University were enrolled in this study. The source device was a single intrauterine tube of Fletcher applicator, all 3 tubes of Fletcher applicator and vaginal applicator. Each patient was scanned by CT before treatment, and the target areas and organs-at-risk were delineated by doctors. DTDC parameters were modified in the step of 0.1. A total of 11 plans were developed from DTDC=0 to DTDC=1, and the plans were normalized to DTDC=0 plan to obtain the corresponding values. The V（150）, V（200） of CTV, D2 ccof bladder and rectum, total dwell time, planned modulation indexes were compared, and the effects of DTDC parameter modification on 3 D afterloading plan were analyzed. Results When using vaginal applicator, a single intrauterine tube of Fletcher applicator,all 3 tubes of Fletcher applicator, with the increase of DTDC, the V（150） and V（200） of CTV were increased to 105% and 109%, 102%and 104%, 115% and 120%, respectively; and the D2 ccin rectum and bladder were increased/decreased to 101% and 102%, 99%and 99%, 115% and 101%, respectively. The total dwell time of DTDC=1 plan using vaginal applicator, a single intrauterine tube of Fletcher applicator and 3 tubes of Fletcher applicator reached 96%, 97% and 104% of that in DTDC=0 plan, respectively.Conclusion To provide a more reasonable treatment plans for patients, the optimal DTDC parameters should be selected based on different source devices used in 3 D afterloading plan for cervical cancer.
作者
纪天龙
赵晶
李权
李光
JI Tianlong;ZHAO Jing;LI Quan;LI Guang(Department of Radiation Oncology,the First Hospital of China Medical University,Shenyang 110001,China)
出处
《中国医学物理学杂志》
CSCD
2018年第8期900-904,共5页
Chinese Journal of Medical Physics
关键词
宫颈癌
近距离治疗
模拟退火
驻留时间离差限制参数
三维后装
cervical cancer
brachytherapy
simulated annealing
dwell time deviation constraint parameters
three-dimensional afterloading
