Study of Monte Carlo Simulator for Estimation of Anti-Scatter Grid Physical Characteristics on IEC 60627:2013-Based

摘要

The anti-scatter grid (grid) is a major component of X-ray imaging devices, improving the quality of the image by removing X-rays scattered while passing through the subject. However, problems such as image distortions or increasing the dose of a patient unnecessarily may result if the grid is not suitable for a specific digital x-ray receptor (detector.) Selecting a suitable grid can take significant work and testing due to the wide range of specifications and physical characteristic of both grid and digital imaging x-ray detectors. In order to reduce the time cost and to improve the accuracy of selecting a suitable grid, this study implemented a Monte Carlo simulation for estimating the physical characteristics of the grid and verified the accuracy of the result by comparing with the physical characteristics of the actual grid. For the verification, this study compared the estimated physical characteristics with the measured physical characteristics for ten (10) grids with different specifications. The physical characteristics were measured at RQR (Radiation Qualities in Radiation Beams emerging from the X-ray Source Assembly) 4/6/8/9 of the Radiation conditions and analyzed Transmission of Primary radiation (Tp), Transmission of Total radiation (Tt) and Transmission of Scattered radiation (Ts) of the physical characteristics of the grid. As a result of the analysis, less than 1% average deviation between simulation and physical measurement was observed with all ten (10) grids. The changes of the physical characteristics as the specifications (line density and ratio) of the grid changed were also evaluated, and found to have a Pearson's correlation coefficient of 0.998 between simulation and measurements. From the above results, the proposed program in this paper is judged reasonable as a grid physical characteristics prediction program.