首页> 外文期刊>Radiation oncology >Two-step intensity modulated arc therapy (2-step IMAT) with segment weight and width optimization
【24h】

Two-step intensity modulated arc therapy (2-step IMAT) with segment weight and width optimization

机译:两段式强度调制弧光疗法(两段式IMAT),具有分段重量和宽度优化功能

获取原文
       

摘要

Background 2-step intensity modulated arc therapy (IMAT) is a simplified IMAT technique which delivers the treatment over typically two continuous gantry rotations. The aim of this work was to implement the technique into a computerized treatment planning system and to develop an approach to optimize the segment weights and widths. Methods 2-step IMAT was implemented into the Prism treatment planning system. A graphical user interface was developed to generate the plan segments automatically based on the anatomy in the beam's-eye-view. The segment weights and widths of 2-step IMAT plans were subsequently determined in Matlab using a dose-volume based optimization process. The implementation was tested on a geometric phantom with a horseshoe shaped target volume and then applied to a clinical paraspinal tumour case. Results The phantom study verified the correctness of the implementation and showed a considerable improvement over a non-modulated arc. Further improvements in the target dose uniformity after the optimization of 2-step IMAT plans were observed for both the phantom and clinical cases. For the clinical case, optimizing the segment weights and widths reduced the maximum dose from 114% of the prescribed dose to 107% and increased the minimum dose from 87% to 97%. This resulted in an improvement in the homogeneity index of the target dose for the clinical case from 1.31 to 1.11. Additionally, the high dose volume V105 was reduced from 57% to 7% while the maximum dose in the organ-at-risk was decreased by 2%. Conclusions The intuitive and automatic planning process implemented in this study increases the prospect of the practical use of 2-step IMAT. This work has shown that 2-step IMAT is a viable technique able to achieve highly conformal plans for concave target volumes with the optimization of the segment weights and widths. Future work will include planning comparisons of the 2-step IMAT implementation with fixed gantry intensity modulated radiotherapy (IMRT) and commercial IMAT implementations.
机译:背景两步强度调制电弧治疗(IMAT)是一种简化的IMAT技术,通常可在两个连续的机架旋转中进行治疗。这项工作的目的是将该技术实施到计算机化的治疗计划系统中,并开发出一种方法来优化段的权重和宽度。方法将两步式IMAT实施到Prism治疗计划系统中。开发了图形用户界面以根据光束的眼睛视图中的解剖结构自动生成计划段。随后在Matlab中使用基于剂量-体积的优化过程确定了两步IMAT计划的分段权重和宽度。该实现在具有马蹄形目标体积的几何体模上进行了测试,然后应用于临床脊柱旁肿瘤病例。结果幻像研究验证了实施的正确性,并显示出与非调制电弧相比有相当大的改进。对于幻影和临床病例,在优化两步IMAT计划后,观察到目标剂量均匀性的进一步改善。对于临床情况,优化段的重量和宽度可将最大剂量从处方剂量的114%降低到107%,并将最小剂量从87%增加到97%。这导致临床病例目标剂量的均一性指数从1.31提高到1.11。此外,高剂量体积V105从57%降低至7%,而有风险器官中的最大剂量降低2%。结论本研究中实现的直观且自动的计划过程增加了实际使用两步IMAT的前景。这项工作表明,两步IMAT是一种可行的技术,能够通过优化段的权重和宽度来实现凹目标体积的高度保形计划。未来的工作将包括计划比较两步IMAT实施与固定龙门调强放疗(IMRT)和商业IMAT实施。

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