Neighborhood search approaches to beam orientation optimization in intensity modulated radiation therapy treatment planning
Neighborhood search approaches to beam orientation optimization in intensity modulated radiation therapy treatment planning
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DOI：
10.1007/s10898-008-9286-x
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发表时间：
2008-12-01
影响因子：
1.8
通讯作者：
Dempsey, James F.
中科院分区：
文献类型：
--
作者：
Aleman, Dionne M.;Kumar, Arvind;Dempsey, James F.
调强放射治疗 (IMRT) 治疗计划问题由几个通常按顺序解决的子问题组成。我们寻求结合两个子问题：光束方向优化（BOO）问题和注量图优化（FMO）问题。 BOO 问题是选择波束方向以向患者提供辐射的问题。 FMO 问题是确定每个光束中每个子束的辐射强度或注量的问题。 FMO 问题的解决方案衡量的是波束组的质量，但之前的大多数 BOO 研究都依赖启发式和近似法来衡量波束组的质量。与这些研究相反，我们使用给定波束组可达到的治疗计划质量的精确测量，这确保在我们的模拟退火算法的情况下收敛到全局最优，在我们的局部搜索算法的情况下确保收敛到局部最优。我们还开发了一种新的邻域结构，可以使用模拟退火和局部搜索算法实现更快的收敛，从而减少获得良好解决方案所需的时间。最后，我们凭经验表明，我们可以生成临床上可接受的治疗计划，其需要的光束比当前实践更少。这可能会减少治疗时间，这是 IMRT 的一个重要临床考虑因素。
The intensity modulated radiation therapy (IMRT) treatment planning problem consists of several subproblems which are typically solved sequentially. We seek to combine two of the subproblems: the beam orientation optimization (BOO) problem and the fluence map optimization (FMO) problem. The BOO problem is the problem of selecting the beam orientations to deliver radiation to the patient. The FMO problem is the problem of determining the amount of radiation intensity, or fluence, of each beamlet in each beam. The solution to the FMO problem measures the quality of a beam set, but the majority of previous BOO studies rely on heuristics and approximations to gauge the quality of the beam set. In contrast with these studies, we use an exact measure of the treatment plan quality attainable using a given beam set, which ensures convergence to a global optimum in the case of our simulated annealing algorithm and a local optimum in the case of our local search algorithm. We have also developed a new neighborhood structure that allows for faster convergence using our simulated annealing and local search algorithms, thus reducing the amount of time required to obtain a good solution. Finally, we show empirically that we can generate clinically acceptable treatment plans that require fewer beams than in current practice. This may reduce the length of treatment time, which is an important clinical consideration in IMRT.