Computer simulation of x-ray scattering characteristics for medical image diagnosis

X-ray diagnosis depends on the intensity of transmitted and scattered waves in X-ray propagation in biomedical media. X-ray is scattered and absorbed by tissues, such as fat, bone and internal organs. However, image processing for medical diagnosis, based on the scattering and absorption characteristics of these tissues in X-ray spectrum is not so much studied. To obtain precise information of tissues in a living body, the accurate characteristics of scattering and absorption are required. In this paper, X-ray scattering and absorption in biomedical media are studied using 2-dimensional FDTD method. As a result of computer simulation, the intensities of transmitted and scattered waves are presented numerically. The scattering intensity is compared with the result of 3-dimensional statistical electromagnetic theory. In FDTD method, the size of analysis space is very limited by the performance of available computers. The way of computation to overcome this limitation is also shown. The theoretical result shows relatively good approximation by considering proper parameters. (author)