Klein E E
Mallinkrodt Institute of Radiology, Radiation Oncology Center, St. Louis, MO 63110, USA.
Med Dosim. 1997 Fall;22(3):213-4. doi: 10.1016/s0958-3947(97)00020-4.
The current versions of the CMS treatment planning systems, the FOCUS system for three dimensional planning, and Modulex for two dimensional planning, both require modeling dynamic wedges as filters. In this paper we describe methods for generating dynamic wedge filters for treatment planning. In our previous work with dynamic wedge we used measured data to back project the filter that would have delivered the wedge shaped isodoses. With the current version of Enhanced Dynamic Wedge, we use the segmented treatment table (STT) to create filters. For each wedge angle we created a 30 cm filter, for which the field is truncated by blocks according to the dynamic jaw settings. We found the filters provided isodoses that were within 2 degrees of the measured angles. Central axis dose was within 1% due to the fact the system does not account for beam hardening. Although an undesirable solution to model dynamic wedging, we found the filter method to be workable.
CMS治疗计划系统的当前版本，用于三维计划的FOCUS系统和用于二维计划的Modulex系统，都需要将动态楔形建模为滤波器。在本文中，我们描述了用于治疗计划生成动态楔形滤波器的方法。在我们之前关于动态楔形的工作中，我们使用测量数据来反向投影能够产生楔形等剂量线的滤波器。对于当前版本的增强动态楔形，我们使用分段治疗床（STT）来创建滤波器。对于每个楔形角度，我们创建了一个30厘米的滤波器，其射野根据动态准直器设置由挡块截断。我们发现这些滤波器提供的等剂量线与测量角度相差在2度以内。由于系统未考虑射束硬化，中心轴剂量在1%以内。尽管将动态楔形建模是一种不理想的解决方案，但我们发现滤波器方法是可行的。
