A full-scale clinical prototype for proton range verification using prompt gamma-ray spectroscopy.
A full-scale clinical prototype for proton range verification using prompt gamma-ray spectroscopy.
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DOI：
10.1088/1361-6560/aad513
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发表时间：
2018-09-17
影响因子：
3.5
通讯作者：
Verburg JM
中科院分区：
文献类型：
--
作者：
Hueso-González F;Rabe M;Ruggieri TA;Bortfeld T;Verburg JM
我们提出了一个全尺寸的临床原型系统，用于体内范围验证质子铅笔束使用提示伽玛射线光谱方法。该检测系统由8个LaBr3闪烁体和一个钨准直器组成，安装在一个旋转框架上。定制的电子和校准算法已经开发用于测量能量和时间分辨伽玛射线能谱在质子照射期间在临床剂量率。利用实验确定的核反应截面和gpu加速蒙特卡罗模拟，为每个单独的铅笔束创建了预期伽马射线发射的详细模型。质子铅笔束的绝对范围是通过最小化测量值和模型之间的差异来确定的，将光束的绝对范围和被照射物质的元素浓度作为自由参数。该系统的特点是在临床类似的情况下，用扫描铅笔光束照射不同的幻影。0.9 Gy的剂量被递送到5×10×10 cm3的靶上，光束电流为2na入射到靶上。使用不同的距离移器和材料来测试验证方法的鲁棒性，并计算检测距离的精度。在半径为10 mm、深度为10 mm的圆柱形区域内聚集铅笔束光斑时，确定了远端能量层每个光斑的绝对质子范围，平均统计精度为1.1 mm，置信水平为95%，平均系统偏差为0.5 mm。我们引入的小范围误差被成功检测到，即使元素组成的大差异也不影响范围验证的准确性。这些结果表明我们的系统适合在我们即将进行的临床研究中进行患者治疗期间的范围验证。
We present a full-scale clinical prototype system for in vivo range verification of proton pencil-beams using the prompt gamma-ray spectroscopy method. The detection system consists of eight LaBr3 scintillators and a tungsten collimator, mounted on a rotating frame. Custom electronics and calibration algorithms have been developed for the measurement of energy- and time-resolved gamma-ray spectra during proton irradiation at a clinical dose rate. Using experimentally determined nuclear reaction cross sections and a GPU-accelerated Monte Carlo simulation, a detailed model of the expected gamma-ray emissions is created for each individual pencil-beam. The absolute range of the proton pencil-beams is determined by minimizing the discrepancy between the measurement and this model, leaving the absolute range of the beam and the elemental concentrations of the irradiated matter as free parameters. The system was characterized in a clinical-like situation by irradiating different phantoms with a scanning pencil-beam. A dose of 0.9 Gy was delivered to a 5×10×10 cm3 target with a beam current of 2 nA incident on the phantom. Different range shifters and materials were used to test the robustness of the verification method and to calculate the accuracy of the detected range. The absolute proton range was determined for each spot of the distal energy layer with a mean statistical precision of 1.1 mm at a 95% confidence level and a mean systematic deviation of 0.5 mm, when aggregating pencil-beam spots within a cylindrical region of 10 mm radius and 10 mm depth. Small range errors that we introduced were successfully detected and even large differences in the elemental composition do not affect the range verification accuracy. These results show that our system is suitable for range verification during patient treatments in our upcoming clinical study.
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影响因子：
3.7
作者：
Capote, R.;Herman, M.;Talou, P.
通讯作者：
Talou, P.
DOI：
10.1109/tns.2016.2622162
发表时间：
2017-01-01
影响因子：
4.4
作者：
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通讯作者：
Enghardt, W.
影响因子：
3.5
作者：
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通讯作者：
Andreo, Pedro
影响因子：
1.3
作者：
Hueso-Gonzalez, F.;Golnik, C.;Pausch, G.
通讯作者：
Pausch, G.
DOI：
10.1016/0168-583x(88)90063-8
发表时间：
1988-09-01
影响因子：
1.3
作者：
RYAN, CG;CLAYTON, E;COUSENS, DR
通讯作者：
COUSENS, DR