• 文献检索
  • 文档翻译
  • 深度研究
  • 学术资讯
  • Suppr Zotero 插件Zotero 插件
  • 邀请有礼
  • 套餐&价格
  • 历史记录
应用&插件
Suppr Zotero 插件Zotero 插件浏览器插件Mac 客户端Windows 客户端微信小程序
定价
高级版会员购买积分包购买API积分包
服务
文献检索文档翻译深度研究API 文档MCP 服务
关于我们
关于 Suppr公司介绍联系我们用户协议隐私条款
关注我们

Suppr 超能文献

核心技术专利：CN118964589B侵权必究
粤ICP备2023148730 号-1Suppr @ 2026

文献检索

告别复杂PubMed语法，用中文像聊天一样搜索，搜遍4000万医学文献。AI智能推荐，让科研检索更轻松。

立即免费搜索

文件翻译

保留排版，准确专业，支持PDF/Word/PPT等文件格式，支持 12+语言互译。

免费翻译文档

深度研究

AI帮你快速写综述，25分钟生成高质量综述，智能提取关键信息，辅助科研写作。

立即免费体验

兆伏级光子束在癌症治疗中电子污染的评估：蒙特卡罗研究

Evaluation of electron contamination in cancer treatment with megavoltage photon beams: monte carlo study.

作者信息

Seif F, Bayatiani M R

机构信息

Associate Professor, Department of Medical Physics and Radiotherapy, Arak University of Medical Sciences and Khansari Hospital, Arak, Iran;

出版信息

J Biomed Phys Eng. 2015 Mar 4;5(1):31-8. eCollection 2015 Mar.

PMID:25973409
原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC4417618/
Abstract

BACKGROUND

Megavoltage beams used in radiotherapy are contaminated with secondary electrons. Different parts of linac head and air above patient act as a source of this contamination. This contamination can increase damage to skin and subcutaneous tissue during radiotherapy. Monte Carlo simulation is an accurate method for dose calculation in medical dosimetry and has an important role in optimization of linac head materials. The aim of this study was to calculate electron contamination of Varian linac.

MATERIALS AND METHOD

The 6MV photon beam of Varian (2100 C/D) linac was simulated by Monte Carlo code, MCNPX, based on its company's instructions. The validation was done by comparing the calculated depth dose and profiles of simulation with dosimetry measurements in a water phantom (error less than 2%). The Percentage Depth Dose (PDDs), profiles and contamination electron energy spectrum were calculated for different therapeutic field sizes (5×5 to 40×40 cm(2)) for both linacs.

RESULTS

The dose of electron contamination was observed to rise with increase in field size. The contribution of the secondary contamination electrons on the surface dose was 6% for 5×5 cm(2) to 27% for 40×40 cm(2), respectively.

CONCLUSION

Based on the results, the effect of electron contamination on patient surface dose cannot be ignored, so the knowledge of the electron contamination is important in clinical dosimetry. It must be calculated for each machine and considered in Treatment Planning Systems.

摘要

背景

放射治疗中使用的兆伏级射束会被二次电子污染。直线加速器机头的不同部位以及患者上方的空气是这种污染的来源。这种污染会在放射治疗期间增加对皮肤和皮下组织的损伤。蒙特卡罗模拟是医学剂量学中剂量计算的一种准确方法，在直线加速器机头材料的优化中具有重要作用。本研究的目的是计算瓦里安直线加速器的电子污染情况。

材料与方法

根据瓦里安公司的说明，使用蒙特卡罗代码MCNPX对瓦里安（2100 C/D）直线加速器的6MV光子束进行模拟。通过将模拟计算得到的深度剂量和剂量分布与水模体中的剂量学测量结果进行比较来进行验证（误差小于2%）。计算了两种直线加速器不同治疗野尺寸（5×5至40×40 cm²）的百分深度剂量（PDDs）、剂量分布和污染电子能谱。

结果

观察到电子污染剂量随野尺寸的增加而升高。二次污染电子对表面剂量的贡献分别为5×5 cm²时的6%至40×40 cm²时的27%。

结论

基于这些结果，电子污染对患者表面剂量 的影响不可忽视，因此在临床剂量学中了解电子污染情况很重要。必须针对每台机器进行计算并在治疗计划系统中予以考虑。

https://cdn.ncbi.nlm.nih.gov/pmc/blobs/184e/4417618/b706cc827383/jbpe-5-31-g011.jpg
https://cdn.ncbi.nlm.nih.gov/pmc/blobs/184e/4417618/ca25b13a8348/jbpe-5-31-g001.jpg
https://cdn.ncbi.nlm.nih.gov/pmc/blobs/184e/4417618/2212ba14cf41/jbpe-5-31-g002.jpg
https://cdn.ncbi.nlm.nih.gov/pmc/blobs/184e/4417618/71239095e8d9/jbpe-5-31-g003.jpg
https://cdn.ncbi.nlm.nih.gov/pmc/blobs/184e/4417618/48f35bc6485f/jbpe-5-31-g004.jpg
https://cdn.ncbi.nlm.nih.gov/pmc/blobs/184e/4417618/15bbcc7bddae/jbpe-5-31-g005.jpg
https://cdn.ncbi.nlm.nih.gov/pmc/blobs/184e/4417618/15e065146929/jbpe-5-31-g006.jpg
https://cdn.ncbi.nlm.nih.gov/pmc/blobs/184e/4417618/8ccef9c334db/jbpe-5-31-g007.jpg
https://cdn.ncbi.nlm.nih.gov/pmc/blobs/184e/4417618/0afe3f45fdfa/jbpe-5-31-g008.jpg
https://cdn.ncbi.nlm.nih.gov/pmc/blobs/184e/4417618/c903b9494594/jbpe-5-31-g009.jpg
https://cdn.ncbi.nlm.nih.gov/pmc/blobs/184e/4417618/cd9b13d03886/jbpe-5-31-g010.jpg
https://cdn.ncbi.nlm.nih.gov/pmc/blobs/184e/4417618/b706cc827383/jbpe-5-31-g011.jpg
https://cdn.ncbi.nlm.nih.gov/pmc/blobs/184e/4417618/ca25b13a8348/jbpe-5-31-g001.jpg
https://cdn.ncbi.nlm.nih.gov/pmc/blobs/184e/4417618/2212ba14cf41/jbpe-5-31-g002.jpg
https://cdn.ncbi.nlm.nih.gov/pmc/blobs/184e/4417618/71239095e8d9/jbpe-5-31-g003.jpg
https://cdn.ncbi.nlm.nih.gov/pmc/blobs/184e/4417618/48f35bc6485f/jbpe-5-31-g004.jpg
https://cdn.ncbi.nlm.nih.gov/pmc/blobs/184e/4417618/15bbcc7bddae/jbpe-5-31-g005.jpg
https://cdn.ncbi.nlm.nih.gov/pmc/blobs/184e/4417618/15e065146929/jbpe-5-31-g006.jpg
https://cdn.ncbi.nlm.nih.gov/pmc/blobs/184e/4417618/8ccef9c334db/jbpe-5-31-g007.jpg
https://cdn.ncbi.nlm.nih.gov/pmc/blobs/184e/4417618/0afe3f45fdfa/jbpe-5-31-g008.jpg
https://cdn.ncbi.nlm.nih.gov/pmc/blobs/184e/4417618/c903b9494594/jbpe-5-31-g009.jpg
https://cdn.ncbi.nlm.nih.gov/pmc/blobs/184e/4417618/cd9b13d03886/jbpe-5-31-g010.jpg
https://cdn.ncbi.nlm.nih.gov/pmc/blobs/184e/4417618/b706cc827383/jbpe-5-31-g011.jpg

相似文献

1
Evaluation of electron contamination in cancer treatment with megavoltage photon beams: monte carlo study.兆伏级光子束在癌症治疗中电子污染的评估：蒙特卡罗研究
J Biomed Phys Eng. 2015 Mar 4;5(1):31-8. eCollection 2015 Mar.
2
Bone and mucosal dosimetry in skin radiation therapy: a Monte Carlo study using kilovoltage photon and megavoltage electron beams.皮肤放射治疗中的骨和粘膜剂量学：使用千伏级光子和兆伏级电子束的蒙特卡罗研究。
Phys Med Biol. 2012 Jun 21;57(12):3885-99. doi: 10.1088/0031-9155/57/12/3885. Epub 2012 May 30.
3
SU-E-T-499: Validation of the Varian Generic Phase Space Files for Monte Carlo Calculations of Dose Distributions for the TrueBeam Linac Head.SU-E-T-499：瓦里安通用相空间文件用于TrueBeam直线加速器机头剂量分布蒙特卡罗计算的验证
Med Phys. 2012 Jun;39(6Part17):3820. doi: 10.1118/1.4735588.
4
Photonuclear dose calculations for high-energy photon beams from Siemens and Varian linacs.西门子和瓦里安直线加速器高能光子束的光核剂量计算。
Med Phys. 2003 Aug;30(8):1990-2000. doi: 10.1118/1.1590436.
5
Electron contamination modeling and reduction in a 1 T open bore inline MRI-linac system.1T开放式内联MRI直线加速器系统中的电子污染建模与减少
Med Phys. 2014 May;41(5):051708. doi: 10.1118/1.4871618.
6
Determination of the initial beam parameters in Monte Carlo linac simulation.蒙特卡罗直线加速器模拟中初始束流参数的确定。
Med Phys. 2006 Apr;33(4):850-8. doi: 10.1118/1.2168433.
7
Modelling of electron contamination in clinical photon beams for Monte Carlo dose calculation.用于蒙特卡洛剂量计算的临床光子束中电子污染的建模。
Phys Med Biol. 2004 Jun 21;49(12):2657-73. doi: 10.1088/0031-9155/49/12/013.
8
Surface dosimetry for oblique tangential photon beams: a Monte Carlo simulation study.斜切向光子束的表面剂量测定：一项蒙特卡罗模拟研究。
Med Phys. 2008 Jan;35(1):70-6. doi: 10.1118/1.2818956.
9
A geometrical model for the Monte Carlo simulation of the TrueBeam linac.用于TrueBeam直线加速器蒙特卡罗模拟的几何模型。
Phys Med Biol. 2015 Jun 7;60(11):N219-29. doi: 10.1088/0031-9155/60/11/N219. Epub 2015 May 18.
10
Characterizing magnetically focused contamination electrons by off-axis irradiation on an inline MRI-Linac.通过在线磁共振引导直线加速器的离轴辐照来描述受磁聚焦的污染电子。
J Appl Clin Med Phys. 2022 Jun;23(6):e13591. doi: 10.1002/acm2.13591. Epub 2022 Mar 25.

引用本文的文献

1
Application of a model-based water-equivalent EPID image conversion algorithm for linac beam QA.基于模型的水等效电子射野影像装置（EPID）图像转换算法在直线加速器束流质量保证中的应用。
J Appl Clin Med Phys. 2025 Aug;26(8):e70210. doi: 10.1002/acm2.70210.
2
Investigating the Impact of Knee Prosthesis in Patients' Body on Radiation Dose Distribution: A Monte Carlo Approach.探究膝关节假体对患者体内辐射剂量分布的影响：一种蒙特卡罗方法。
J Biomed Phys Eng. 2019 Jun 1;9(3):345-354. doi: 10.31661/jbpe.v0i0.1047. eCollection 2019 Jun.
3
Monte-Carlo simulation of the Siemens Artiste linear accelerator flat 6 MV and flattening-filter-free 7 MV beam line.

本文引用的文献

1
On bolus for megavoltage photon and electron radiation therapy.用于兆伏光子和电子放射治疗的推注剂量。
Med Dosim. 2013 Autumn;38(3):268-73. doi: 10.1016/j.meddos.2013.02.007. Epub 2013 Apr 9.
2
Measurement of magnetic fields produced by a "magnetic deflector" for the removal of electron contamination in radiotherapy.用于去除放射治疗中电子污染的“磁偏转器”所产生磁场的测量。
Australas Phys Eng Sci Med. 2006 Dec;29(4):321-7. doi: 10.1007/BF03178398.
3
Measurement and production of electron deflection using a sweeping magnetic device in radiotherapy.
西门子艺术家直线加速器平 6MV 和均整滤过自由 7MV 射线束线的蒙特卡罗模拟。
PLoS One. 2019 Jan 8;14(1):e0210069. doi: 10.1371/journal.pone.0210069. eCollection 2019.
放射治疗中使用扫描磁装置测量和产生电子偏转
Australas Phys Eng Sci Med. 2006 Sep;29(3):260-6. doi: 10.1007/BF03178575.
4
Characterization of electron contamination in megavoltage photon beams.
Med Phys. 2005 May;32(5):1281-92. doi: 10.1118/1.1895793.
5
Are neutrons responsible for the dose discrepancies between Monte Carlo calculations and measurements in the build-up region for a high-energy photon beam?在高能光子束的积累区域，蒙特卡罗计算与测量之间的剂量差异是由中子引起的吗？
Phys Med Biol. 2002 Sep 7;47(17):3251-61. doi: 10.1088/0031-9155/47/17/313.
6
Energy spectra, angular spread, fluence profiles and dose distributions of 6 and 18 MV photon beams: results of monte carlo simulations for a varian 2100EX accelerator.6和18兆伏光子束的能谱、角分布、注量剖面和剂量分布：瓦里安2100EX加速器的蒙特卡罗模拟结果
Phys Med Biol. 2002 Apr 7;47(7):1025-46. doi: 10.1088/0031-9155/47/7/303.
7
A monte carlo approach to electron contamination sources in the Saturne-25 and -41.一种用于研究Saturne - 25和 - 41中电子污染源的蒙特卡罗方法。
Phys Med Biol. 2001 Sep;46(9):2435-46. doi: 10.1088/0031-9155/46/9/312.
8
Comparison of measured and Monte Carlo calculated dose distributions from the NRC linac.美国核管理委员会直线加速器测量剂量分布与蒙特卡罗计算剂量分布的比较。
Med Phys. 2000 Oct;27(10):2256-66. doi: 10.1118/1.1290714.