Study on the Energy Response of EDR2 Film to Scanning Proton and Carbon Ion Beams
SUN Wei1,2,3, LI Yongqiang1,2,3
1. Department of Medical Physics, Shanghai Proton and Heavy Ion Center, Shanghai 201321, China;
2. Shanghai Key Laboratory of Radiation Oncology, Shanghai 201321, China;
3. Shanghai Engineering Research Center of Proton and Heavy Ion Radiation Therapy, Shanghai 201321, China
Abstract：Objective To study the energy response of EDR2 film to scanning Proton and Carbon Ion Beams. Methods The same
EDR2 film was irradiated by 9 kinds of uniform proton and carbon ion beams with a scanning range of 5 cm×5 cm, the same energy
and different doses. After scanning, the average value of pixels within a 2 cm × 2 cm area was obtained using Image J. The average
value of pixels was converted to optical density (OD) value by calculation, and the slope of the fitted line representing the dose
response factor (DRF) for the specific energy of protons and carbon ions was acquired. The DRFs of energies were compared and
analyzed, and the response curves of EDR2 film to protons and carbon ions with different energies were obtained. Results For proton
highest energy (218.56 MeV) and lowest energy (53.04 MeV), the DRF values were 0.52 OD/Gy and 0.40 OD/Gy. For carbon ion
highest energy (424.89 MeV/u) and lowest energy (97.87 MeV/u), the DRF values were 0.25 OD/Gy and 0.11 OD/Gy.
The DRF of EDR2 film for protons and carbon ions increased with beam energy increasing. Conclusion The EDR2 film presents
significant variations of energy dependency when measuring the dose of carbon ions and protons. When using EDR2 film to measure
the dose of protons and carbon ions with different energies, it is necessary to calibrate the energy response to improve the accuracy.
孙威1,2,3，李永强1,2,3. EDR2胶片对扫描质子碳离子束的
能量响应研究[J]. 中国医疗设备, 2024, 39(1): 56-60.
SUN Wei1,2,3, LI Yongqiang1,2,3. Study on the Energy Response of EDR2 Film to Scanning Proton and Carbon Ion Beams. China Medical Devices, 2024, 39(1): 56-60.
