Niemierko A, Goitein M
Department of Radiation Medicine, Massachusetts General Hospital, Boston 02114.
Med Phys. 1990 Sep-Oct;17(5):753-62. doi: 10.1118/1.596473.
We analyze the influence of sampling technique on the accuracy of estimating irradiated volumes, dose-volume histograms and tumor control and normal tissue complication probabilities. The sampling techniques we consider are uniform distribution of points on a regular Cartesian grid and random selection of points. For three-dimensional treatment planning, random sampling leads to a significant reduction in estimation error and/or in the number of calculation points necessary to achieve a required accuracy. We discuss advantages and drawbacks of random sampling, as compared to sampling on a regular grid. It is suggested that, in practical situations, at least 50 times fewer randomly sampled points per organ/volume of interest are needed for fast estimation of complication probability with the same accuracy, i.e., not exceeding 5% (within 95% confidence limits) in the worst case.
我们分析了采样技术对估计照射体积、剂量体积直方图以及肿瘤控制和正常组织并发症概率准确性的影响。我们考虑的采样技术是在规则笛卡尔网格上的点的均匀分布和点的随机选择。对于三维治疗计划，随机采样会显著降低估计误差和/或为达到所需精度所需的计算点数。我们讨论了与在规则网格上采样相比，随机采样的优缺点。建议在实际情况中，对于每个感兴趣的器官/体积，以相同精度快速估计并发症概率所需的随机采样点数至少少50倍，即在最坏情况下不超过5%（在95%置信限内）。
