Material efficiency studies for a Compton camera designed to measure characteristic prompt gamma rays emitted during proton beam radiotherapy.
Material efficiency studies for a Compton camera designed to measure characteristic prompt gamma rays emitted during proton beam radiotherapy.
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DOI：
10.1088/0031-9155/56/10/010
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发表时间：
2011-05-21
影响因子：
3.5
通讯作者：
Beddar S
中科院分区：
文献类型：
--
作者：
Robertson D;Polf JC;Peterson SW;Gillin MT;Beddar S
在质子辐照期间从生物组织发射的即时伽马射线携带剂量和光谱信息，这些信息可以帮助治疗验证，并提供受照射组织的生物反应的指示。康普顿相机能够确定伽马射线的来源和能量。然而，质子治疗过程中的快速伽马监测需要新的康普顿相机设计，在组织被治疗性质子轰击时产生的高伽马能量下表现良好。在这项研究中，我们优化了用于快速伽马探测的三级康普顿相机的材料和几何结构，并计算了这种探测器的理论效率。本研究评估的材料包括锗、锗酸铋(BGO)、NaI、氙气、硅和溴化镧(LaBr3)。对于每种材料，每个探测器阶段的尺寸都进行了优化，以产生最大数量的相关相互作用。这些结果被用来预测各种多材质相机的效率。然后，计算了最有希望的多材料相机的理论探测效率，这些相机是由50到250 MeV的治疗性质子束照射的组织等效体模发出的光子。优化的探测器级具有10×10cm2的横向范围，前两级的厚度取决于探测器材料。第三阶段的厚度固定为10 cm，不考虑材料。效率最高的单材质相机是由Ge(3 Cm)和BGO(2.5 cm)组成。每入射质子的效率分别为1.15×10−4和9.5 8×10−5。最有效的多材料相机设计包括两个初始阶段的Ge(3 Cm)和最后一个阶段的BGO，其理论效率为每个入射质子1.26×10−4。
Prompt gamma rays emitted from biological tissues during proton irradiation carry dosimetric and spectroscopic information that can assist with treatment verification and provide an indication of the biological response of the irradiated tissues. Compton cameras are capable of determining the origin and energy of gamma rays. However, prompt gamma monitoring during proton therapy requires new Compton camera designs that perform well at the high gamma energies produced when tissues are bombarded with therapeutic protons. In this study we optimize the materials and geometry of a three-stage Compton camera for prompt gamma detection and calculate the theoretical efficiency of such a detector. The materials evaluated in this study include germanium, bismuth germanate (BGO), NaI, xenon, silicon and lanthanum bromide (LaBr3). For each material, the dimensions of each detector stage were optimized to produce the maximum number of relevant interactions. These results were used to predict the efficiency of various multi-material cameras. The theoretical detection efficiencies of the most promising multi-material cameras were then calculated for the photons emitted from a tissue-equivalent phantom irradiated by therapeutic proton beams ranging from 50 to 250 MeV. The optimized detector stages had a lateral extent of 10 × 10 cm2 with the thickness of the initial two stages dependent on the detector material. The thickness of the third stage was fixed at 10 cm regardless of material. The most efficient single-material cameras were composed of germanium (3 cm) and BGO (2.5 cm). These cameras exhibited efficiencies of 1.15 × 10−4 and 9.58 × 10−5 per incident proton, respectively. The most efficient multi-material camera design consisted of two initial stages of germanium (3 cm) and a final stage of BGO, resulting in a theoretical efficiency of 1.26 × 10−4 per incident proton.
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影响因子：
3.5
作者：
Peterson SW;Robertson D;Polf J
通讯作者：
Polf J
影响因子：
3.8
作者：
Clasie, Ben;Wroe, Andrew;Rosenfeld, Anatoly
通讯作者：
Rosenfeld, Anatoly
DOI：
10.1016/s0360-3016(01)02826-7
发表时间：
2002-05-01
影响因子：
7
作者：
Schneider, U;Agosteo, S;Besserer, J
通讯作者：
Besserer, J
DOI：
10.1016/s0168-9002(97)00048-x
发表时间：
1997-04-11
影响因子：
1.4
作者：
Brun, R;Rademakers, F
通讯作者：
Rademakers, F
影响因子：
3.5
作者：
Polf, J. C.;Peterson, S.;Trache, L.
通讯作者：
Trache, L.