Chant Tim, Ramachandran Prabhakar
Department of Radiation Oncology, Therapeutic Physics, Cancer Services, Princess Alexandra Hospital, Woolloongabba, Queensland, Australia.
J Med Phys. 2023 Oct-Dec;48(4):392-397. doi: 10.4103/jmp.jmp_107_23. Epub 2023 Dec 5.
Radiation dosimeters play a crucial role in radiation oncology by accurately measuring radiation dose, ensuring precise and safe radiation therapy. This study presents the design and development of a low-cost printed circuit board (PCB) dosimeter and an integrated electrometer with sensitivity optimized for dose rates intended for use in megavoltage radiation therapy. The PCB dosimeter was designed in KiCad, and it uses a low-cost S5MC-13F general-purpose 1 kV 5A power diode as a radiation detector. The dosimeter is calibrated against a known dose derived from an ionization chamber and tested for dose linearity, dose rate dependence, field size dependence, and detector orientation dependence. The observed average dose differences between the delivered and measured doses for most measurements were found to be < 1.1%; the dose rate linearity between 100 MU/min and 1400 MU/min was found to be within 1.3%. This low-cost architecture could successfully be adapted further for a scalable, cost-effective dosimetry solution through firmware or circuit design.
辐射剂量计在放射肿瘤学中起着至关重要的作用，它通过精确测量辐射剂量，确保放射治疗的精确性和安全性。本研究介绍了一种低成本印刷电路板（PCB）剂量计以及一种集成静电计的设计与开发，该静电计针对兆伏级放射治疗中预期的剂量率进行了灵敏度优化。PCB剂量计在KiCad中进行设计，它使用低成本的S5MC - 13F通用1 kV 5A功率二极管作为辐射探测器。该剂量计根据电离室得出的已知剂量进行校准，并测试剂量线性、剂量率依赖性、射野大小依赖性和探测器方向依赖性。大多数测量中，所输送剂量与测量剂量之间观察到的平均剂量差异<1.1%；在100 MU/分钟至1400 MU/分钟之间的剂量率线性在1.3%以内。通过固件或电路设计，这种低成本架构可以成功地进一步适用于可扩展、具有成本效益的剂量测定解决方案。
