Simulation of respiratory motion effect on dose distributions in three-dimensional radiotherapy

VernacularTitle:模拟呼吸运动对三维放疗剂量分布的影响
Author: Zhenle FEI ; Zhenyang NIU ; Zhijie LI ; Lei WANG
Publication Type:Journal Article
Keywords: Respiratory motion; Three-dimensional conformal radiotherapy; Intensitymodulated radiotherapy; Dose distribution
From: Chinese Journal of Radiation Oncology 2012;(6):554-556
CountryChina
Language:Chinese
Abstract: Objective To evaluate the effects of respiratory on dose distributions in threedimensional conformal radiotherapy (3 DCRT) and intensity-modulated radiotherapy (IMRT).Methods The dose distributions were measured with a PTW 2D-ARRAY seven29 placed on a home-made moving platform to simulate the respirator.Dosimetric comparisions for 3DCRT and IMRT plans were performed by means of Gamma analysis with 3％ and 3 mm,respectively.Dose distribution measured for static treatment plans.Results The respiratory could reduce the target does and conformal index.The r pass rate (3％3 mm in 3 DCRT was greater than it in IMRT ((53.58 ± 0.74) ％,(30.71 ± 1.00) ％,t =57.91,P ＜ 0.01).The failed points were mainly near the field edge,but located in the whole target volumes for IMRT plans.Conclusions It is undesirable to use IMRT techniques for tumors with large motion amplitude.3DCRT can give a reliable dose distribution by reasonably selecting the PTV margin.