Gomà Carles, Marinelli Marco, Safai Sairos, Verona-Rinati Gianluca, Würfel Jan
Centre for Proton Therapy, Paul Scherrer Institute, Villigen PSI, Switzerland; Department of Physics, Swiss Federal Institute of Technology Zurich, Zurich, Switzerland.
INFN-Dipartimento di Ingegneria Industriale, Università di Roma 'Tor Vergata', Roma, Italy.
Z Med Phys. 2016 Mar;26(1):88-94. doi: 10.1016/j.zemedi.2015.08.003. Epub 2015 Aug 29.
In this work, the performance of a microDiamond detector in a scanned proton beam is studied and its potential role in the dosimetric characterization of proton pencil beams is assessed. The linearity of the detector response with the absorbed dose and the dependence on the dose-rate were tested. The depth-dose curve and the lateral dose profiles of a proton pencil beam were measured and compared to reference data. The feasibility of calibrating the beam monitor chamber with a microDiamond detector was also studied. It was found the detector reading is linear with the absorbed dose to water (down to few cGy) and the detector response is independent of both the dose-rate (up to few Gy/s) and the proton beam energy (within the whole clinically-relevant energy range). The detector showed a good performance in depth-dose curve and lateral dose profile measurements; and it might even be used to calibrate the beam monitor chambers-provided it is cross-calibrated against a reference ionization chamber. In conclusion, the microDiamond detector was proved capable of performing an accurate dosimetric characterization of proton pencil beams.
在这项工作中，研究了微金刚石探测器在扫描质子束中的性能，并评估了其在质子笔形束剂量学表征中的潜在作用。测试了探测器响应与吸收剂量的线性关系以及对剂量率的依赖性。测量了质子笔形束的深度剂量曲线和横向剂量分布，并与参考数据进行了比较。还研究了用微金刚石探测器校准束流监测电离室的可行性。结果发现，探测器读数与水的吸收剂量呈线性关系（低至几厘戈瑞），探测器响应与剂量率（高达几戈瑞/秒）和质子束能量（在整个临床相关能量范围内）均无关。该探测器在深度剂量曲线和横向剂量分布测量中表现良好；并且只要与参考电离室进行交叉校准，甚至可能用于校准束流监测电离室。总之，微金刚石探测器被证明能够对质子笔形束进行准确的剂量学表征。
