TY - JOUR
T1 - Polarisation-based coincidence event discrimination
T2 - an in silico study towards a feasible scheme for Compton-PET
AU - Toghyani, M.
AU - Gillam, J. E.
AU - McNamara, A. L.
AU - Kuncic, Z.
PY - 2016/8/7
Y1 - 2016/8/7
N2 - Current positron emission tomography (PET) systems use temporally localized coincidence events discriminated by energy and time-of-flight information. The two annihilation photons are in an entangled polarisation state and, in principle, additional information from the polarisation correlation of photon pairs could be used to improve the accuracy of coincidence classification. In a previous study, we demonstrated that in principle, the polarization correlation information could be transferred to an angular correlation in the distribution of scattered photon pairs in a planar Compton camera system. In the present study, we model a source-phantom-detector system using Geant4 and we develop a coincidence classification scheme that exploits the angular correlation of scattered annihilation quanta to improve the accuracy of coincidence detection. We find a 22% image quality improvement in terms of the peak signal-to-noise ratio when scattered coincidence events are discriminated solely by their angular correlation, thus demonstrating the feasibility of this novel classification scheme. By integrating scatter events (both single-single and single-only) with unscattered coincidence events discriminated using conventional methods, our results suggest that Compton-PET may be a promising candidate for optimal emission tomographic imaging.
AB - Current positron emission tomography (PET) systems use temporally localized coincidence events discriminated by energy and time-of-flight information. The two annihilation photons are in an entangled polarisation state and, in principle, additional information from the polarisation correlation of photon pairs could be used to improve the accuracy of coincidence classification. In a previous study, we demonstrated that in principle, the polarization correlation information could be transferred to an angular correlation in the distribution of scattered photon pairs in a planar Compton camera system. In the present study, we model a source-phantom-detector system using Geant4 and we develop a coincidence classification scheme that exploits the angular correlation of scattered annihilation quanta to improve the accuracy of coincidence detection. We find a 22% image quality improvement in terms of the peak signal-to-noise ratio when scattered coincidence events are discriminated solely by their angular correlation, thus demonstrating the feasibility of this novel classification scheme. By integrating scatter events (both single-single and single-only) with unscattered coincidence events discriminated using conventional methods, our results suggest that Compton-PET may be a promising candidate for optimal emission tomographic imaging.
KW - Monte Carlo simulations
KW - polarization
KW - positron emission tomography
KW - Compton imaging
UR - http://www.scopus.com/inward/record.url?scp=84979555709&partnerID=8YFLogxK
U2 - 10.1088/0031-9155/61/15/5803
DO - 10.1088/0031-9155/61/15/5803
M3 - Article
C2 - 27405797
AN - SCOPUS:84979555709
SN - 0031-9155
VL - 61
SP - 5803
EP - 5817
JO - Physics in Medicine and Biology
JF - Physics in Medicine and Biology
IS - 15
ER -