Abstract Objective To study the influence of the angle of multileaf collimator leaves on segments (control point for sliding windows) number and monitor units in intensity-modulated radiotherapy (IMRT) plan optimization. Methods 10 cases undergone IMRT with rectangle target volume were choosed, 2 plan were designed with step and shot technique and sliding windows technique for running direction of collimator with target long axis vertical and parallel respectively, compared the plans with similar optimization parameters for different angle of the collimator. Results The number of segments and monitor units increased by 52.8% and 49.6% more than longitudinal direction of leaf collimator with static IMRT respectively, there appeared significant difference (P=0.000);and the number of segments and monitor units increased by 58.2% and 61.9% more than longitudinal direction of leaf collimator with dynamic IMRT respectively, there appeared significant difference (P=0.000). Conclusions For the optimization of IMRT based on multileaf collimator, the direction of collimator perpendicular to the target long axis, there could be obviously decrease the number of monitor units, shorten the treatment time, improve the treatment efficiency with similar dose distribution.
LI Chang-hu,ZHANG Chun-li,XU Li-ming et al. The influence of multileaf collimator angle on delivery efficiency for IMRT treatment[J]. Chinese Journal of Radiation Oncology, 2013, 22(6): 482-484.
LI Chang-hu,ZHANG Chun-li,XU Li-ming et al. The influence of multileaf collimator angle on delivery efficiency for IMRT treatment[J]. Chinese Journal of Radiation Oncology, 2013, 22(6): 482-484.
[1] Samuelsson A, Karl-Axel J. Intensity modulated radiotherapy treatment planning for dynamic multileaf collimator delivery:influence of different parameters on dose distributions. Radiother Oncol,2003,66:19-28. [2] 戴建荣,胡逸民.调强放疗的计划设计.中国医疗器械信息,2005,11:9-12. [3] Kamath S, Sahni S, Li J, et al. Leaf sequencing algorithms for segmented multileaf collimation. Phys Med Biol,2003,48:307-324. [4] Kamath S, Sahni S, Palta J, et al. Algorithms for optimal sequencing of dynamic multileaf collimator. Phys Med Biol,2004,49:33-54. [5] Chui CS, Chan MF, Yorke E, et al. Delivery of intensity modulated radiation therapy with a conventional multileaf collimator:comparison of dynamic and segmental. Med Phys,2001,12:2441-2449. [6] 杨瑞杰,戴建荣,胡逸民.调强放射治疗的计划优化.中国医疗器械信息,2005,11:13-16. [7] 王闯,戴建荣,胡逸民.射野方向优化方法.中华放射肿瘤学杂志,2004,13:104-106. [8] Wang C, Dai J, Hu Y. Optimization of beam orientations and beam weights for conformal radiotherapy using mixed integer programming. Phys Med Biol,2003,48:4065-4076. [9] Yang RJ, Dai JR, Yang Y, et al. Beam orientation optimization for intensity-modulated radiation therapy using mixed integer programming. Phys Med Biol,2006,51:3653-3666. [10] Stein J, Mohan R. Number and orientation of beams in intensity modulated radiation therapy. Med Phys,1997,24:149-160. [11] Engel K. A new algorithm for optimal multileaf collimator field segmentation. Dis Appl Mathemat,2005,152:35-51. [12] 余光伟,王连聪,李侠,等.多叶准直器参数对调强放疗计划的影响.中华放射肿瘤学杂志,2010,19:163-165. [13] 常熙,徐志勇,周莉钧,等.鼻咽癌逆向调强计划中照射野方向和照射野数目对剂量分布的影响.中国癌症杂志,2007,17:324-328. [14] 白瞳,陈进琥,尹勇,等.直线加速器二级准直器在鼻咽癌调强放疗计划设计中的应用研究.中华放射肿瘤学杂志,2010,19:355-357. [15] 曹征,李红霞,鲍杨漪.前列腺癌调强计划改变多叶准直器角度对直肠和膀胱剂量的影响.中国医学物理学杂志,2010,27:1844-1847. [16] Chapek J, Tobler M, Toy BJ, et al. Optimization of collimator parameters to reduce rectal dose in intensity-modulated prostate treatment planning. Med Dosimet,2005,30:205-212. [17] Losasso T. IMRT delivery performance with a varian multileaf collimator. Int J Radiat Onco Biol Phys,2008,71:85-88.
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