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arXiv · 2506.07230

First positronium imaging using $^{44}$Sc with the J-PET scanner: a case study on the NEMA-Image Quality phantom

Manish Das·Sushil Sharma·Aleksander Bilewicz·Jarosław Choiński·Neha Chug·Catalina Curceanu·Eryk Czerwiński·Jakub Hajduga·Sharareh Jalali·Krzysztof Kacprzak·Tevfik Kaplanoglu·Łukasz Kapłon·Kamila Kasperska·Aleksander Khreptak·Grzegorz Korcyl·Tomasz Kozik·Karol Kubat·Deepak Kumar·Anoop Kunimmal Venadan·Edward Lisowski·Filip Lisowski·Justyna Medrala-Sowa·Simbarashe Moyo·Wiktor Mryka·Szymon Niedźwiecki·Piyush Pandey·Szymon Parzych·Alessio Porcelli·Bartłomiej Rachwał·Elena Perez del Rio·Martin Rädler·Axel Rominger·Kuangyu Shi·Magdalena Skurzok·Anna Stolarz·Tomasz Szumlak·Pooja Tanty·Keyvan Tayefi Ardebili·Satyam Tiwari·Kavya Valsan Eliyan·Rafał Walczak·Ermias Yitayew Beyene·Ewa Ł. Stępień·Paweł Moskal
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Abstract

Positronium Lifetime Imaging (PLI), an emerging extension of conventional positron emission tomography (PET) imaging, offers a novel window for probing the submolecular properties of biological tissues by imaging the mean lifetime of the positronium atom. Currently, the method is under rapid development in terms of reconstruction and detection systems. Recently, the first in vivo PLI of the human brain was performed using the J-PET scanner utilizing the $^{68}$Ga isotope. However, this isotope has limitations due to its comparatively low prompt gamma yields, which is crucial for positronium lifetime measurement. Among alternative radionuclides, $^{44}$Sc stands out as a promising isotope for PLI, characterized by a clinically suitable half-life (4.04 hours) emitting 1157 keV prompt gamma in 100% cases after the emission of the positron. This study reports the first experimental demonstration of PLI with $^{44}$Sc, carried out on a NEMA-Image Quality (IQ) phantom using the Modular J-PET tomograph-the first plastic scintillators-based PET scanner.

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Manish Das, Sushil Sharma, Aleksander Bilewicz, Jarosław Choiński, Neha Chug, Catalina Curceanu, Eryk Czerwiński, Jakub Hajduga, Sharareh Jalali, Krzysztof Kacprzak, Tevfik Kaplanoglu, Łukasz Kapłon, Kamila Kasperska, Aleksander Khreptak, Grzegorz Korcyl, Tomasz Kozik, Karol Kubat, Deepak Kumar, Anoop Kunimmal Venadan, Edward Lisowski, Filip Lisowski, Justyna Medrala-Sowa, Simbarashe Moyo, Wiktor Mryka, Szymon Niedźwiecki, Piyush Pandey, Szymon Parzych, Alessio Porcelli, Bartłomiej Rachwał, Elena Perez del Rio, Martin Rädler, Axel Rominger, Kuangyu Shi, Magdalena Skurzok, Anna Stolarz, Tomasz Szumlak, Pooja Tanty, Keyvan Tayefi Ardebili, Satyam Tiwari, Kavya Valsan Eliyan, Rafał Walczak, Ermias Yitayew Beyene, Ewa Ł. Stępień, Paweł Moskal. 2025-09-29. First positronium imaging using $^{44}$Sc with the J-PET scanner: a case study on the NEMA-Image Quality phantom. https://doi.org/10.1109/trpms.2025.3621554

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