医疗卫生装备2017,Vol.38Issue(3):90-93,4.DOI:10.7687/J.ISSN1003-8868.2017.03.090
多叶准直器重力效应对调强放射治疗剂量的影响研究
Study of dose variations induced by MLC weight effect for IMRT delivery
摘要
Abstract
Objective To evaluate dose variations induced by gravity of multi-leaf collimator to provide references for clinical intensity-modulated radiotherapy.Methods Two-dimensional dose distributions in the central plane of IMRT fields were measured by use of a 2D ion chamber array.All measurements were repeated at two collimator angles (C=0 and 90°),for each of the following gantry angles:G=0 and 270°.Comparisons were made to dose distributions generated at G=0°and their differences were analyzed using gamma index analysis (3%/3 mm and 1%/1 mm).Results Under the radiation field of 10 cm×10 cm,the gamma passing rate was higher than 99% for 3% 3 mm anch close to 95% for 1%/1mm Under a 3%/3mm error standard,the average matching rate for step & shoot fields was (96.46±0.33)% and for DMLC fields was (94.67±0.54)% at C=0°;The average matching rate for step & shoot fields was (94.59±0.47)% and for DMLC fields was (92.60±0.52)% at C=90°.Under a 1%/1mm error standard,the average matching rate for step & shoot fields was (89.83 ±1.06)% and for DMLC fields was (85.84±0.57)% at C=0°;The average matching rate for step & shoot fields was (86.91 ±1.71)% and for DMLC fields was (83.89±0.69)% at C=90°.Concusion MLC weight effect affects IMRT delivery dose,and DMLC fields are more sensitive to gravity than step & shoot fields.关键词
多叶准直器/重力效应/调强放射治疗/剂量/γ通过率Key words
multi-leaf collimator/weight effect/IMRT/dose/gamma passing rate分类
医药卫生引用本文复制引用
卢晓光,王峻峰,刘飞,李定宇,梅齐,胡广原..多叶准直器重力效应对调强放射治疗剂量的影响研究[J].医疗卫生装备,2017,38(3):90-93,4.基金项目
湖北省自然基金面上项目(2014CFB366) (2014CFB366)