Medical Physics Program, Department of Physics and Applied Physics, University of Massachusetts Lowell, Lowell, MA 01854, United States of America. Department of Radiation Oncology, Brigham and Women's Hospital, Dana Farber Cancer Institute and Harvard Medical School, Boston, MA 02115, United States of America. These authors contributed equally to this work.
Phys Med Biol. 2019 Apr 29;64(9):095019. doi: 10.1088/1361-6560/ab12aa.
We have developed a novel method for fast image simulation of flat panel detectors, based on the photon energy deposition efficiency and the optical spread function (OSF). The proposed method, FastEPID, determines the photon detection using photon energy deposition and replaces particle transport within the detector with precalculated OSFs. The FastEPID results are validated against experimental measurement and conventional Monte Carlo simulation in terms of modulation transfer function (MTF), signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), contrast, and relative difference of pixel value, obtained with a slanted slit image, Las Vegas phantom, and anthropomorphic pelvis phantom. Excellent agreement is observed between simulation and measurement in all cases. Without degrading image quality, the FastEPID method is capable of reducing simulation time up to a factor of 150. Multiple applications, such as imager design optimization for planar and volumetric imaging, are expected to benefit from the implementation of the FastEPID method.
我们基于光子能量沉积效率和光学扩展函数（OSF）开发了一种用于快速平板探测器图像模拟的新方法。所提出的方法 FastEPID 使用光子能量沉积来确定光子检测，并使用预先计算的 OSF 替换探测器内的粒子输运。FastEPID 的结果在调制传递函数（MTF）、信噪比（SNR）、对比噪声比（CNR）、对比度以及斜狭缝图像、拉斯维加斯体模和人体骨盆体模获得的像素值的相对差值方面，通过实验测量和传统的蒙特卡罗模拟进行了验证。在所有情况下，模拟和测量之间都观察到极好的一致性。FastEPID 方法在不降低图像质量的情况下，能够将模拟时间缩短至原来的 150 分之一。平面和容积成像的成像仪设计优化等多种应用有望受益于 FastEPID 方法的实施。
