...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Radiotherapy and oncology: Journal of the European Society for Therapeutic Radiology and Oncology >Effect of tertiary multileaf collimator (MLC) on foetal dose during three-dimensional conformal radiation therapy (3DCRT) of a brain tumour during pregnancy.
【24h】

Effect of tertiary multileaf collimator (MLC) on foetal dose during three-dimensional conformal radiation therapy (3DCRT) of a brain tumour during pregnancy.

机译：三叶准直器（MLC）对妊娠期脑肿瘤的三维共形放射治疗（3DCRT）期间胎儿剂量的影响。

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

BACKGROUND AND PURPOSE: The aim of this work was to measure the dose to foetus both in vivo and in vitro during three-dimensional conformal radiation therapy (3DCRT) in a pregnant patient with a pituitary adenoma. The study was then extended to assess the components contributing to the foetal dose such as collimator scatter, internal scatter, head leakage, wedge scatter and multileaf collimator (MLC) effect. PATIENTS AND METHODS: A 30-year-old pregnant woman with a non-functioning pituitary macroadenoma was planned for 3DCRT with 6MV X-ray using four equally weighted MLC-shaped non-coplanar wedged portals. In vivo dosimetry was carried out using thermoluminescent (TL) phosphor powder, which was placed at different positions on the patient, corresponding to different locations in the uterus and also at external os. In vitro measurements were also performed on a simulated phantom using the same set-up parameters and beam arrangement to verify the in vivo measured dose. Experiments were carried out to measure the respective contributions of different components towards peripheral dose. RESULTS: In vitro measured dose to foetus was found to be slightly more than that of in vivo measurement with a maximum of 0.044% of the prescribed dose of 45Gy, which corresponded to 0.0199+/-0.0008Gy. Thermoluminescence dosimeter (TLD) kept at the external os of the patient showed a dose of 0.031% of the prescribed dose. Among the various components of the peripheral dose (foetal dose) measured, head leakage was found to be the leading cause contributing 52%, followed by wedge scatter (31%), collimator scatter (14%) and internal scatter (13%). The use of MLC reduced not only the volume of normal brain irradiation as compared to open fields but also the peripheral dose by 10%. CONCLUSION: Radiotherapy of brain tumours during pregnancy poses a unique clinical situation and decisions to deliver radiotherapy should be taken after detailed in vitro and in vivo dosimetric measurements. Our findings suggest that the beam arrangement using 3-4-fields generally used for 3DCRT of brain tumour with MLC for optimal coverage can be employed for pregnant patients even in early trimester. A possible increase in foetal dose from wedges to a large extent can be compensated with the use of MLC.
机译：背景与目的：这项工作的目的是在垂体腺瘤的孕妇中进行三维共形放射治疗（3DCRT）期间在体内和体外测量胎儿的剂量。然后扩大研究范围，以评估有助于胎儿剂量的成分，例如准直器散射，内部散射，头部泄漏，楔形散射和多叶准直器（MLC）效应。患者和方法：计划将一名30岁的垂体无功能性腺瘤功能正常的孕妇用于3DCRT，并使用4个相等权重的MLC形非共面楔形入口进行6MV X线检查。使用热致发光（TL）荧光粉进行体内剂量测定，将其放置在患者的不同位置，对应于子宫中的不同位置以及外部os。还使用相同的设置参数和光束布置在模拟体模上进行了体外测量，以验证体内测得的剂量。进行实验以测量不同组分对外周剂量的各自贡献。结果：发现体外测得的胎儿剂量略高于体内测得的剂量，最大为45Gy处方剂量的0.044％，相当于0.0199 +/- 0.0008Gy。保持在患者体外的热发光剂量计（TLD）的剂量为处方剂量的0.031％。在所测量的外围剂量（足部剂量）的各个组成部分中，头部泄漏被发现是主要原因，占52％，其次是楔形散射（31％），准直器散射（14％）和内部散射（13％）。与开阔地带相比，MLC的使用不仅使正常的脑部照射量减少了10％，而且外围剂量也减少了10％。结论：妊娠期脑肿瘤的放射治疗构成了独特的临床情况，应在详细的体外和体内剂量测量后决定进行放射治疗。我们的发现表明，即使在妊娠早期，也可以使用通常用于脑肿瘤3DCRT并带有MLC的3-4-场光束进行最佳覆盖。 MLC的使用可以弥补楔形胎儿的剂量增加。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号