Four-dimensional dose calculation (4D-DC) is crucial for predicting the dosimetric outcome in the presence of intra-fractional organ motion. Time-resolved dosimetry can provide significant insights into 4D pencil beam scanning dose accumulation and is therefore irreplaceable for benchmarking 4D-DC. In this study a novel approach of time-resolved dosimetry using five PinPoint ionization chambers (ICs) embedded in an anthropomorphic dynamic phantom was employed and validated against beam delivery details. Beam intensity variations as well as the beam delivery time structure were well reflected with an accuracy comparable to the temporal resolution of the IC measurements. The 4D dosimetry approach was further applied for benchmarking the 4D-DC implemented in the RayStation 6.99 treatment planning system. Agreement between computed values and measurements was investigated for (i) partial doses based on individual breathing phases, and (ii) temporally distributed cumulative doses. Fo...

中文翻译：

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时间分辨剂量学用于验证PBS质子治疗中4D剂量的计算

二维剂量计算（4D-DC）对于在存在分数内器官运动的情况下预测剂量测定结果至关重要。时间分辨的剂量测定法可以提供有关4D铅笔射束扫描剂量累积的重要见解，因此对于基准4D-DC来说是不可替代的。在这项研究中，采用了一种新的时间分辨剂量测定方法，该方法使用了五个拟人动态人体模型中嵌入的PinPoint电离室（IC），并针对射束传输细节进行了验证。光束强度的变化以及光束传输时间的结构都可以很好地反映出来，其精度与IC测量的时间分辨率相当。4D剂量学方法进一步应用于对RayStation 6.99治疗计划系统中实施的4D-DC进行基准测试。对于（i）基于各个呼吸阶段的部分剂量和（ii）时间分布的累积剂量，研究了计算值与测量值之间的一致性。佛...