Proton Therapy Center, National Cancer Center, Goyang 10408, Korea.
Department of Radiation Oncology, Myongji Hospital, Goyang 10475, Korea.
Sensors (Basel). 2022 Aug 4;22(15):5819. doi: 10.3390/s22155819.
Several detectors have been developed to measure radiation doses during radiotherapy. However, most detectors are not flexible. Consequently, the airgaps between the patient surface and detector could reduce the measurement accuracy. Thus, this study proposes a dose measurement system based on a flexible copper indium gallium selenide (CIGS) solar cell. Our system comprises a customized CIGS solar cell (with a size 10 × 10 cm2 and thickness 0.33 mm), voltage amplifier, data acquisition module, and laptop with in-house software. In the study, the dosimetric characteristics, such as dose linearity, dose rate independence, energy independence, and field size output, of the dose measurement system in therapeutic X-ray radiation were quantified. For dose linearity, the slope of the linear fitted curve and the R-square value were 1.00 and 0.9999, respectively. The differences in the measured signals according to changes in the dose rates and photon energies were <2% and <3%, respectively. The field size output measured using our system exhibited a substantial increase as the field size increased, contrary to that measured using the ion chamber/film. Our findings demonstrate that our system has good dosimetric characteristics as a flexible in vivo dosimeter. Furthermore, the size and shape of the solar cell can be easily customized, which is an advantage over other flexible dosimeters based on an a-Si solar cell.
已经开发出几种探测器来测量放射治疗过程中的辐射剂量。然而，大多数探测器不具有灵活性。因此，患者表面和探测器之间的气隙可能会降低测量精度。因此，本研究提出了一种基于柔性铜铟镓硒（CIGS）太阳能电池的剂量测量系统。我们的系统包括一个定制的 CIGS 太阳能电池（尺寸为 10×10cm2，厚度为 0.33mm）、电压放大器、数据采集模块以及带有内部软件的笔记本电脑。在研究中，对治疗 X 射线辐射中剂量测量系统的剂量线性、剂量率独立性、能量独立性和射野大小输出等剂量学特性进行了量化。对于剂量线性，线性拟合曲线的斜率和 R 平方值分别为 1.00 和 0.9999。根据剂量率和光子能量的变化，测量信号的差异分别小于 2%和小于 3%。与使用电离室/胶片测量的结果相反，我们系统测量的射野大小输出随着射野的增大而显著增加。我们的研究结果表明，我们的系统作为一种柔性体内剂量计具有良好的剂量学特性。此外，太阳能电池的尺寸和形状可以很容易地定制，这是优于其他基于非晶硅太阳能电池的柔性剂量计的优势。
