This work investigates the positional single photon incidence response（P-SPIR） to provide an accurate point spread function（PSF）-contained system matrix and its incorporation within the image reconstruction framew...This work investigates the positional single photon incidence response（P-SPIR） to provide an accurate point spread function（PSF）-contained system matrix and its incorporation within the image reconstruction framework.Based on the Geant4 Application for Emission Tomography（GATE） simulation,P-SPIR theory takes both incidence angle and incidence position of the gamma photon into account during crystal subdivision,instead of only taking the former into account,as in single photon incidence response（SPIR）.The response distribution obtained in this fashion was validated using Monte Carlo simulations.In addition,two-block penetration and normalization of the response probability are introduced to improve the accuracy of the PSF.With the incorporation of the PSF,the homogenization model is then analyzed to calculate the spread distribution of each line-of-response（LOR）.A primate PET scanner,Eplus-260,developed by the Institute of High Energy Physics,Chinese Academy of Sciences（IHEP）,was employed to evaluate the proposed method.The reconstructed images indicate that the P-SPIR method can effectively mitigate the depth-of-interaction（DOI） effect,especially at the peripheral area of field-of-view（FOV）.Furthermore,the method can be applied to PET scanners with any other structures and list-mode data format with high flexibility and efficiency.展开更多
基金Supported by National Natural Science Foundation of China(81301348)China Postdoctoral Science Foundation(2015M570154)
文摘This work investigates the positional single photon incidence response（P-SPIR） to provide an accurate point spread function（PSF）-contained system matrix and its incorporation within the image reconstruction framework.Based on the Geant4 Application for Emission Tomography（GATE） simulation,P-SPIR theory takes both incidence angle and incidence position of the gamma photon into account during crystal subdivision,instead of only taking the former into account,as in single photon incidence response（SPIR）.The response distribution obtained in this fashion was validated using Monte Carlo simulations.In addition,two-block penetration and normalization of the response probability are introduced to improve the accuracy of the PSF.With the incorporation of the PSF,the homogenization model is then analyzed to calculate the spread distribution of each line-of-response（LOR）.A primate PET scanner,Eplus-260,developed by the Institute of High Energy Physics,Chinese Academy of Sciences（IHEP）,was employed to evaluate the proposed method.The reconstructed images indicate that the P-SPIR method can effectively mitigate the depth-of-interaction（DOI） effect,especially at the peripheral area of field-of-view（FOV）.Furthermore,the method can be applied to PET scanners with any other structures and list-mode data format with high flexibility and efficiency.
