放射治疗剂量计算算法中外轮廓对剂量结果的影响分析

<title>pression of Contours to Dose Results Calculated with some Algorithms

目的探讨在放射治疗剂量计算过程中,不同算法的计算结果对外轮廓勾画的依赖程度。方法选取CT影象资料3份,精确勾画出所有靶区范围后,采用不同的轮廓勾画方法勾画外轮廓,在相同的照射条件下用手工计算、Clarkson算法、FFT算法以及超点算法来计算剂量分布。结果 手工计算结果差异最大,Clarkson算法有一定差异,而FFT以及超点算法则基本没有差别。结论 外轮廓对剂量计算的影响随算法的精度不同而不同,在利用精确算法计算剂量分布时,外轮廓只影响射野的源皮距而几乎不影响剂量计算结果。

<abstract>jective To valuate the impression of the contours to the dose results during the process of radiotherapy dose calculation. Methods 3 groups of CT images including head, thorax and belly were selected. After the targets were drawn precisely, two different ways were adopted to draw the contours and the doses were calculated with hand, Clarkson algorithm, FFT algorithm and Superposition algorithm. Result The dose results calculated by hand had great error, Clarkson, little error but with FFT and Superposition, there were almost no difference. Conclusions The impression of the contour to the dose calculation is different with different algorithm. With some precise and 3-D algorithm, the impression can be ignored.