Abstract

Info

Title:: Eliminating lateral response artifact for EBT3 radiochromic film digitization

Author(s):: BAI Kai1; 2; 3; 4; ZHANG Pengcheng5; HUANG Shengcong2; 3; 4; QI Ning5; LI Qiang2; 3; 4; LIU Xinguo2; 3; 4; 1. School of Nuclear Science and Technology, Lanzhou University, Lanzhou 730000, China 2. Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000, China 3. Key Laboratory of Heavy Ion Radiation Biology and Medicine of Chinese Academy of Sciences, Lanzhou 730000, China 4. Gansu Provincial Key Laboratory of Basic Research on Heavy Ion Radiation Application in Medicine, Lanzhou 730000, China 5. Department of Radiotherapy, the First Hospital of Lanzhou University, Lanzhou 730000, China

Keywords:: Keywords: EBT3 radiochromic film digitization anti-reflective glass lateral response artifact net optical density

Abstract:: Abstract: Objective To eliminate the lateral response artifact during EBT3 radiochromic film digitization and optimize the treatment plan verification results using EBT3 film. Methods The EBT3 films were digitalized with a scanner covered with a double-side coated anti-reflective glass. The lateral response artifact was eliminated using the parabola function which was obtained by fitting the relationship between the net optical densities and their positions on the scanner window. Then the net optical densities were converted into doses via dose calibration curve. The method was tested with a QA plan with a large irradiation field, and the gamma-index distribution was analyzed. Results The gamma passing rate (3%/3 mm, for dose greater than or equal 0.1 Gy) between planned dose profile and corrected film dose profile was 95% which was 3% higher than the uncorrected film dose profile. Conclusion The proposed method can effectively eliminate the lateral response artifact and improve the gamma passing rate of QA plan verification using EBT3 film.