Lu X Q, Chin L M
Joint Center for Radiation Therapy, Department of Radiation Oncology, Harvard Medical School, Boston, Massachusetts 02115.
Med Phys. 1993 Jan-Feb;20(1):151-61. doi: 10.1118/1.597096.
Sampling techniques using randomly distributed points and regular Cartesian grids were compared for the evaluation of volume, dose-volume histogram, tumor control, and normal tissue complication probabilities in radiation treatments. Particularly, the uncertainties associated with each sampling technique in estimating the dose-volume histograms for several dose distributions are analyzed in detail. It is found that the estimation of these parameters using sampling points on a regular Cartesian grid is, in general, significantly more efficient than using random points. This finding is different from other published results. The choice of grid size for sampling was analyzed according to the AAPM recommended uncertainty on the dose delivered to the patient. It was concluded that when grid sampling is used, a grid size of 0.5 cm is adequate for most plans to meet the guidelines.
比较了使用随机分布点和规则笛卡尔网格的采样技术，以评估放射治疗中的体积、剂量体积直方图、肿瘤控制和正常组织并发症概率。特别地，详细分析了每种采样技术在估计几种剂量分布的剂量体积直方图时的不确定性。结果发现，一般来说，使用规则笛卡尔网格上的采样点来估计这些参数比使用随机点要高效得多。这一发现与其他已发表的结果不同。根据美国医学物理师协会（AAPM）推荐的患者所接受剂量的不确定性，分析了采样网格大小的选择。得出的结论是，当使用网格采样时，对于大多数计划而言，0.5厘米的网格大小足以满足指南要求。
