First ex-vivo positronium imaging of tissues with modular J-PET scanner using $^{44}$Sc radionuclide

Karol Kubat; Manish Das; Sushil Sharma; Ermias Y. Beyene; 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; Deepak Kumar; Sumit Kumar Kundu; Anoop Kunimmal-Venadan; Bartosz Leszczyński; Edward Lisowski; Filip Lisowski; Justyna Mędrala-Sowa; Simbarashe Moyo; Wiktor Mryka; Szymon Niedźwiecki; Anand Pandey; Piyush Pandey; Szymon Parzych; Alessio Porcelli; Bartłomiej Rachwał; Martin Rädler; Magdalena Skurzok; Anna Stolarz; Tomasz Szumlak; Pooja Tanty; Keyvan Tayefi Ardebili; Satyam Tiwari; Kavya Valsan Eliyan; Rafał Walczak; Paweł Moskal; Ewa Ł. Stępień

arXiv · 2602.07580

First ex-vivo positronium imaging of tissues with modular J-PET scanner using $^{44}$Sc radionuclide

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Abstract

This study presents the first ex-vivo positronium imaging of human tissues using the modular J-PET scanner with the $^{44}$Sc radionuclide. The $^{44}$Sc isotope was produced via the $^{44}$Ca(p, n)$^{44}$Sc nuclear reaction and used to perform positronium imaging of phantom composed of human adipose tissue, cardiac myxoma tissue, thrombi blood clot, and also porous polymer XAD4, and a certified reference material (CRM) made from fused silica. The experiment demonstrates the suitability of $^{44}$Sc as a positron source for positronium imaging. The performance of J-PET for positronium imaging with $^{44}$Sc was validated by proper reconstruction of the mean orthopositronium lifetime for CRM material and XAD-4 polymer. The mean ortho-positronium (oPs) lifetimes determined for adipose tissue, cardiac myxoma tissues and thrombi were consistent with results of previous experiments. The study highlights the potential $^{44}$Sc radionuclide for positronium lifetime imaging (PLI).

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Karol Kubat, Manish Das, Sushil Sharma, Ermias Y. Beyene, 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, Deepak Kumar, Sumit Kumar Kundu, Anoop Kunimmal-Venadan, Bartosz Leszczyński, Edward Lisowski, Filip Lisowski, Justyna Mędrala-Sowa, Simbarashe Moyo, Wiktor Mryka, Szymon Niedźwiecki, Anand Pandey, Piyush Pandey, Szymon Parzych, Alessio Porcelli, Bartłomiej Rachwał, Martin Rädler, Magdalena Skurzok, Anna Stolarz, Tomasz Szumlak, Pooja Tanty, Keyvan Tayefi Ardebili, Satyam Tiwari, Kavya Valsan Eliyan, Rafał Walczak, Paweł Moskal, Ewa Ł. Stępień. 2026-02-07. First ex-vivo positronium imaging of tissues with modular J-PET scanner using $^{44}$Sc radionuclide. https://arxiv.org/abs/2602.07580

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