GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt, Germany.
Institute of Medical Physics and Radiation Protection (IMPS), THM University of Applied Sciences Giessen, Giessen, Germany.
J Appl Clin Med Phys. 2020 Oct;21(10):227-232. doi: 10.1002/acm2.12996. Epub 2020 Sep 29.
Three-dimensional (3D) dosimetry is a necessity to validate patient-specific treatment plans in particle therapy as well as to facilitate the development of novel treatment modalities. Therefore, a vendor-agnostic water phantom was developed and verified to measure high resolution 3D dose distributions.
The system was experimentally validated at the Marburger Ionenstrahl-Therapiezentrum using two ionization chamber array detectors (PTW Octavius 1500XDR and 1000P) with 150.68 MeV proton and 285.35 MeV/u C beams. The dose distribution of several monoenergetic and complex scanned fields were measured with different step sizes to assess the reproducibility, absolute positioning accuracy, and general performance of the system.
The developed system was successfully validated and used to automatically measure high resolution 3D dose distributions. The reproducibility in depth was better than ±25 micron. The roll and tilt uncertainty of the detector was estimated to be smaller than ±3 mrad.
The presented system performed fully automated, high resolution 3D dosimetry, suitable for the validation of complex radiation fields in particle therapy. The measurement quality is comparable to commercially available systems.
在粒子治疗中，三维（3D）剂量测定对于验证患者特异性治疗计划以及促进新的治疗方式的发展是必要的。因此，开发并验证了一种与供应商无关的水模体，以测量高分辨率的 3D 剂量分布。
该系统在马尔堡离子束治疗中心使用两个电离室阵列探测器（PTW Octavius 1500XDR 和 1000P）进行了实验验证，探测器探测能量为 150.68 MeV 的质子和 285.35 MeV/u 的 C 射线。使用不同的步长测量了几个单能和复杂扫描场的剂量分布，以评估系统的可重复性、绝对定位精度和总体性能。
所开发的系统已成功验证并用于自动测量高分辨率 3D 剂量分布。深度方向的重现性优于±25 微米。探测器的滚动和倾斜不确定性估计小于±3 毫弧度。
所提出的系统实现了全自动、高分辨率的 3D 剂量测定，适用于粒子治疗中复杂辐射场的验证。测量质量可与商业可用系统相媲美。
