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arXiv · 2411.08237

Quantitative Imaging of $^{55}\text{Co}$ and $^{18}\text{F}$-Labeled Tracers in a Single "Multiplexed" PET Imaging Session

Sarah J Zou·Irene Lim·Jackson W Foster·Garry Chinn·Hailey A Houson·Suzanne E. Lapi·Jianghong Rao·Craig S Levin
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Abstract

In this study, we explore the use of Co-55 as a radioisotope for multiplexed PET (mPET) by utilizing its emission of a prompt gamma-ray in cascade with a positron during decay. We leverage the prompt-gamma signal to generate triple coincidences for a Co-55-labeled tracer, allowing us to distinguish it from a tracer labeled with a pure positron emitter, such as F-18. By employing triple versus double coincidence detection and signal processing methodology, we successfully separate the Co-55 signal from that of F-18. Phantom studies were conducted to establish the correlation between Co-55 double and triple coincidence counts and Co-55 activity. Additionally, we demonstrate the potential for quantifying hot spots within a warm background produced by both Co-55 and F-18 signals in a single PET scan. Finally, we showcase the ability to simultaneously image two tracers in vivo in a single PET session with mouse models of cancer.

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Sarah J Zou, Irene Lim, Jackson W Foster, Garry Chinn, Hailey A Houson, Suzanne E. Lapi, Jianghong Rao, Craig S Levin. 2024-11-12. Quantitative Imaging of $^{55}\text{Co}$ and $^{18}\text{F}$-Labeled Tracers in a Single "Multiplexed" PET Imaging Session. https://doi.org/10.1109/isbi60581.2025.10980731

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