Byrne J, Lambert G
Regional Medical Physics Department, Newcastle General Hospital, Newcastle upon Tyne, NE4 6BE, UK.
Phys Med Biol. 2004 Sep 7;49(17):N277-85. doi: 10.1088/0031-9155/49/17/n02.
Hounsell and Wilkinson (1997 Phys. Med. Biol. 42 1737-49) have demonstrated that the concept of a scatter-plane source can accurately describe head scatter in irregularly shaped fields produced by the MLC of an Elekta linear accelerator. In these linacs, the solid jaw is below the MLC set and plays no part on defining the view of the main source of head scatter, the flattening filter. A more complicated situation arises for linear accelerator head designs which incorporate a solid upper jaw pair with the MLC jaws further from the source. Application of the Hounsell and Wilkinson technique to these accelerator designs does not achieve the accuracy in the Elekta application. We present a generalized extension to Hounsell and Wilkinson's model and present results for typical treatment field shapes on a Siemens Primus linear accelerator.
洪塞尔和威尔金森（1997年，《物理医学与生物学》42卷，1737 - 1749页）已证明，散射平面源的概念能够准确描述由医科达直线加速器的多叶准直器（MLC）产生的不规则形状射野中的头部散射。在这些直线加速器中，实心准直器位于MLC组件下方，在定义头部散射主要源（即均整器）的视角方面不起作用。对于那些将实心上准直器对与离源更远的MLC准直器相结合的直线加速器头部设计，情况更为复杂。将洪塞尔和威尔金森技术应用于这些加速器设计时，无法达到在医科达直线加速器应用中的精度。我们提出了对洪塞尔和威尔金森模型的广义扩展，并给出了在西门子Primus直线加速器上典型治疗射野形状的结果。
