Coded Aperture and Compton Imaging for the Development of $^{225}$Ac-based Radiopharmaceuticals
Abstract
Targeted alpha-particle therapy (TAT) has great promise as a cancer treatment. Arguably the most promising TAT radionuclide that has been proposed is Ac. The development of Ac-based radiopharmaceuticals has been hampered due to the lack of effective means to study the daughter redistribution of these agents in small animals at the preclinical stage. The ability to directly image the daughters, namely Fr and Bi, via their gamma-ray emissions would be a boon for preclinical studies. That said, conventional medical imaging modalities, including single photon emission computed tomography (SPECT) based on pinhole collimation, cannot be employed due to sensitivity limitations. As an alternative, we propose the use of both coded aperture and Compton imaging with the former modality suited to the 218-keV gamma-ray emission of Fr and the latter suited to the 440-keV gamma-ray emission of Bi. This work includes coded aperture images of Fr and Compton images of Bi in tumor-bearing mice injected with Ac-based radiopharmaceuticals. These results are the first demonstration of visualizing and quantifying the Ac daughters in small animals via coded aperture and Compton imaging and serve as a stepping stone for future radiopharmaceutical studies.
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Cite
@article{arxiv.2212.07631,
title = {Coded Aperture and Compton Imaging for the Development of $^{225}$Ac-based Radiopharmaceuticals},
author = {Emily A. Frame and Kondapa N. Bobba and Donald L. Gunter and Lucian Mihailescu and Anil P. Bidkar and Robert R. Flavell and Kai Vetter},
journal= {arXiv preprint arXiv:2212.07631},
year = {2023}
}