Photon dose calculation incorporating explicit electron transport.
Photon dose calculation incorporating explicit electron transport.
复制标题
结合显式电子传输的光子剂量计算。
DOI：
10.1118/1.597611
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发表时间：
1995
期刊：
影响因子：
3.8
通讯作者：
Wong,JW
中科院分区：
文献类型：
--
作者：
Yu,CX;Mackie,TR;Wong,JW
近年来，在改进光子剂量计算方面取得了重大进展。然而，准确预测的剂量扰动效应附近的界面不同的介质，带电粒子的平衡没有建立，仍然没有解决。此外，原子序数的变化，这会影响二次电子的多库仑散射，不占当前的光子剂量计算算法。由于局域界面效应主要是由于二次电子的扰动，光子-电子级联模型提出了一个包含显式电子输运的计算在非均匀介质中的初级光子剂量分量。初级光子束被视为许多电子笔束的源。后者使用费米-艾格斯理论进行传输。散射光子剂量贡献是用剂量扩散阵列[T. R. Mackie，J.W. Scrimger和J. J. Battista，Med.Phys.12，188-196（1985）]方法。计算结果与Monte Carlo模拟结果和XPS测量结果的比较表明，聚苯乙烯-铝界面附近的位置有很好的一致性。
Significant advances have been made in recent years to improve photon dose calculation. However, accurate prediction of dose perturbation effects near the interfaces of different media, where charged particle equilibrium is not established, remain unsolved. Furthermore, changes in atomic number, which affect the multiple Coulomb scattering of the secondary electrons, are not accounted for by current photon dose calculation algorithms. As local interface effects are mainly due to the perturbation of secondary electrons, a photon–electron cascade model is proposed which incorporates explicit electron transport in the calculation of the primary photon dose component in heterogeneous media. The primary photon beam is treated as the source of many electron pencil beams. The latter are transported using the Fermi–Eyges theory. The scattered photon dose contribution is calculated with the dose spread array [T. R. Mackie, J. W. Scrimger, and J. J. Battista, Med. Phys.12, 188–196 (1985)] approach. Comparisons of the calculation with Monte Carlo simulation and TLD measurements show good agreement for positions near the polystyrene–aluminum interfaces.