A Study Of Photon Count Multispectral CT Simulation Based On Geant4 Monte Carlo Platform

Current CT imaging technology research has from the traditional single energy spectrum CT to the photon counting energy spectrum CT,in view of the photon counting model of energy spectrum CT study has made some progress,but mostly stay in the theoretical stage,also need a lot of experiments to obtain objective data verified,but it requires a lot of time and cost.In order to solve these problems,it is necessary to find a cheap and more efficient experimental method.In this paper,the monte carlo simulation platform is built on the computer by using Geant4 and GATE data packets.(1)By Geant4 and GATE structures,monte carlo simulation platform,the data packets and then build the three layers of scintillation detector,each layer of the probe,respectively,by the same size of three kinds of crystal materials,the use of different crystal on the spectrum of recognition to multiple spectrum under CT measurement data obtained at the same time,and by comparing the spectrum of projection and reconstruction slice images based on the energy spectrum of the multi-layer scintillation detector is verified the feasibility of CT.(2)constructed with tellurium cadmium zinc(CZT)as the material of photon counting detectors,simulation based on photon counting detector spectral CT imaging process,and through the calculation of projection of energy spectrum and reconstruction slice images verify the feasibility of this process,the energy spectrum threshold selection effects on the projected image.In order to solve the problem of high noise of narrow spectrum CT measurement data,the noise reduction algorithm based on nonlinear partial differential equation(PM)is used to suppress the noise of measurement data,and a good reconstruction result is obtained.