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  • Enhanced positronium lifetime imaging through two-component reconstruction in time-of-flight positron emission tomography
Title: Enhanced positronium lifetime imaging through two-component reconstruction in time-of-flight positron emission tomography
Positronium lifetime imaging (PLI) is a newly demonstrated technique possible with time-of-flight (TOF) positron emission tomography (PET), capable of producing an image reflecting the lifetime of the positron, more precisely ortho-positronium (o-Ps), before annihilation, in addition to the traditional uptake image of the PET tracer. Due to the limited time resolution of TOF-PET systems and the added complexities in physics and statistics, lifetime image reconstruction presents a challenge. Recently, we described a maximum-likelihood approach for PLI by considering only o-Ps. In real-world scenarios, other populations of positrons that exhibit different lifetimes also exist. This paper introduces a novel two-component model aimed at enhancing the accuracy of o-Ps lifetime images. Through simulation studies, we compare this new model with the existing single-component model and demonstrate its superior performance in accurately capturing complex lifetime distributions.  more » « less
Award ID(s):
2318925
PAR ID:
10534169
Author(s) / Creator(s):
; ; ;
Publisher / Repository:
Frontiers
Date Published:
Journal Name:
Frontiers in Physics
Volume:
12
ISSN:
2296-424X
Subject(s) / Keyword(s):
positronium lifetime imaging image reconstruction time-of-flight positron emission tomography two-component model maximum likelihood estimation
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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