Proton Therapy Center, National Cancer Center, Goyang, Korea.
Department of Radiation and Oncology, National Medical Center, Seoul, South Korea.
Med Phys. 2018 Nov;45(11):5277-5282. doi: 10.1002/mp.13149. Epub 2018 Sep 27.
Fabricate an acrylic disk radiation sensor (ADRS) and characterize the photoluminescence signal generated from the optical device as basis for the development and evaluation of a new dosimetry system for pencil beam proton therapy.
Based on the characteristics of the proposed optical dosimetry sensor, we established the relation between the photoluminescence output and the applied dose using an ionization chamber. Then, we obtained the relative integral depth dose profiles using the photoluminescence signal generated by pencil beam irradiation at energies of 99.9 and 162.1 MeV, and compared the results with the curve measured using a Bragg peak ionization chamber.
The relation between the photoluminescence output and applied dose was linear. In addition, the ADRS was dose independent for beam currents up to 6 Gy/min, and the calibration factor for energy was close to 1. Hence, the energy dependence on the optical device can be disregarded. The integral depth dose profiles obtained for the ADRS suitable agreed with the curve measured in the Bragg peak ionization chamber without requiring correction.
These results suggest that the ADRS is suitable for dosimetry measurements in pencil beam scanning, and it will be employed as a low-cost and versatile dosimetry sensor in upcoming developments.
制作丙烯酸盘状辐射传感器（ADRS），并对该光学器件产生的光致发光信号进行特性分析，为开发和评估铅笔束质子治疗新剂量测量系统奠定基础。
基于所提出的光学剂量测量传感器的特点，我们利用离子室建立了光致发光输出与应用剂量之间的关系。然后，我们使用能量为 99.9 和 162.1 MeV 的铅笔束照射产生的光致发光信号获得相对积分深度剂量分布，并将结果与使用布拉格峰电离室测量的曲线进行比较。
光致发光输出与应用剂量之间呈线性关系。此外，ADRS 在高达 6 Gy/min 的束流下与剂量无关，并且能量校准因子接近 1。因此，可以忽略光学器件的能量依赖性。ADRS 获得的积分深度剂量分布与布拉格峰电离室中测量的曲线非常吻合，无需校正。
这些结果表明，ADRS 适用于铅笔束扫描中的剂量测量，并且将作为低成本、多功能的剂量传感器应用于未来的开发中。
