Electron applicator cutouts for radiation therapy electron beam shaping are typically cast from Low Melting Point Alloys (LMPA), such as cerrobend. In this work, we describe the Monte Carlo modelling of novel 3D printed cutouts based on tungsten carbide powder and the resulting dose profiles subject to Elekta Agility electron beams. Cerrobend cutouts were also modelled using the Monte Carlo code EGSnrc. Cerrobend and tungsten carbide cutouts were found to have the same dose profiles within model variance. Computed profiles and percentage depth dose (PDDs) curves of the Elekta Agility accelerator model using standard cutouts in water were found to agree with water tank measurements using gamma criteria of 2%/2mm. The Monte Carlo computed dose profiles of the tungsten carbide cutouts in a polystyrene phantom were also found to agree with liquid-filled ionization chamber array measurements using gamma criteria of 2% / 2mm. We conclude that the tungsten carbide cutouts are clinically equivalent to LMPA cutouts.

中文翻译：

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碳化钨和 LMPA 电子切口：使用蒙特卡罗建模和剂量测量进行比较和验证

用于放射治疗电子束成形的电子施加器切口通常由低熔点合金 (LMPA) 铸造而成，例如 cerrobed。在这项工作中，我们描述了基于碳化钨粉末的新型 3D 打印切口的 Monte Carlo 建模以及受到 Elekta Agility 电子束影响的剂量分布。Cerrobed 切口也使用 Monte Carlo 代码 EGSnrc 建模。发现 Cerrobeb 和碳化钨切口在模型方差内具有相同的剂量分布。发现使用水中标准切口的 Elekta Agility 加速器模型的计算曲线和百分比深度剂量 (PDD) 曲线与使用 2%/2mm 伽马标准的水箱测量值一致。Monte Carlo 计算的聚苯乙烯体模中碳化钨切口的剂量分布也被发现与使用 2% / 2mm 伽马标准的充满液体的电离室阵列测量结果一致。我们得出结论，碳化钨切口在临床上等同于 LMPA 切口。