SPECT에서 재구성한 영상의 개선에 관한 연구

Abstract

In this paper, several methods for image reconstruction were investigated, such as simple back-projection method, inverse radon method and filtered back projection method, which would be effectively applicable to reconstruct the images from SPECT(Single Photon Emission Computed Tomography). Also, the optimum low-pass filter for filtered back-projection method was designed through the variation of cut-off frequency in Hamming filter. The experimental results involved followings: 1) the effective removal of the star effect and the noise in reconstructed images by using the designed filters. 2) the satisfactory images reconstructed by the filtered back-projection scheme. 3) the difference between expected cut-off frequency by simulation and chosen one by subjective evaluation with most meaningful diagnostics. It was shown that the optimal cut-off frequency should be not consistent in all images but varied according to the condition of projection such as SNR(signal to noise ratio) and operation factors determining radioisotope dosage, radio-pharmaceuticals, acquisition collection time.