Costa T, Adolfsson E, Fager M, Lund E
Department of Medicine and Health Sciences, Linköping University, Linköping, Sweden.
Department of Medical Physics and Department of Medical and Health Sciences, Linköping University, Linköping, Sweden.
Radiat Prot Dosimetry. 2019 Dec 31;186(1):83-87. doi: 10.1093/rpd/ncy293.
The specific aim for the characterization of the lithium formate dosimetry system is to determine response and stability in a proton beam. The long-term goal for this investigation is an audit system for proton therapy like the end-to-end dose determinations performed for radiotherapy with photons. For a 150-MeV proton beam, the dose response was found to be linear in the dose interval 0-8.8 Gy. The accuracy of dose reconstruction was controlled in a blind test, in which the dose of 6.63 Gy was measured in samples irradiated with a real dose of 6.70 Gy. The stability was determined by irradiations of sets of four dosimeters every week during 1 month and analyzed at the same day thereafter. The fitting of the fading curve was done with a second-order polynomial resulting in a 6.6% lower value compared to the reference after 31 d.
表征甲酸锂剂量测定系统的具体目标是确定其在质子束中的响应和稳定性。本次研究的长期目标是建立一个质子治疗的审计系统，类似于针对光子放射治疗所进行的端到端剂量测定。对于150 MeV的质子束，发现在0 - 8.8 Gy的剂量区间内剂量响应呈线性。剂量重建的准确性在一次盲测中得到控制，在该盲测中，用6.70 Gy的实际剂量照射样品，测量得到的剂量为6.63 Gy。通过在1个月内每周对四组剂量计进行照射，并在之后同一天进行分析来确定稳定性。衰减曲线的拟合采用二阶多项式，在31天后得到的值比参考值低6.6%。
