First Positronium Lifetime Imaging using 52Mn and 55Co with a plastic-based PET scanner
M. Das, S. Sharma, E. Yitayew Beyene, A. Bilewicz, J. Choiński, N. Chug, C. Curceanu, E. Czerwiński, J. Hajduga, S. Jalali, K. Kacprzak, T. Kaplanoglu, Ł. Kapłon, K. Kasperska, A. Khreptak, G. Korcyl, T. Kozik, K. Kubat, D. Kumar, S. Kumar Kundu, A. Kunimmal Venadan, E. Lisowski, F. Lisowski, J. Medrala-Sowa, S. Moyo, W. Mryka, S. Niedźwiecki, A. Pandey, P. Pandey, S. Parzych, A. Porcelli, B. Rachwał, M. Rädler, N. Rathod, N. Razzaq, A. Rominger, K. Shi, M. Skurzok, M. Słotwiński, A. Stolarz, T. Szumlak, P. Tanty, K. Tayefi Ardebili, S. Tiwari, K. Valsan Eliyan, R. Walczak, E. Ł. Stępień, P. Moskal
abstract
This study demonstrates applicability of 52Mn and 55Co radionuclides for positronium imaging. Positronium Lifetime Imaging
(PLI) extends positron emission tomography by using the lifetime of positronium atoms as a probe of tissue molecular
architecture. However, its practical use requires ?+ emitters that also provide an additional prompt ? ray to mark the positron creation time. In this work, we report the first PLI measurements performed with 52Mn and 55Co using the modular J-PET. Four samples were studied in each experiment: two Certified Reference Materials (polycarbonate and fused silica) and two
human tissues (cardiac myxoma and adipose). The selection of PLI events was based on the registration of two 511 keV
annihilation photons and one prompt gamma in triple coincidence. From the resulting lifetime spectra we extracted the mean
ortho-positronium lifetime ?oPs and the mean positron lifetime ?Tmean for each sample. The measured values of ?oPs in
polycarbonate using both isotopes matches well with the certified reference values. Furthermore, 55Co reproduced identical
results for fused-silica measurements at their respective uncertainty levels. In contrast, measurements with 52Mn in fused silica show a minor deviation, which could be caused by the Parafilm spacer. In myxoma and adipose tissue, the reduced ?oPs values are mainly linked to the long storage history of the samples rather than to the choice of isotope. Comparing peak-to-background ratios and spectral purity, 55Co provides cleaner PLI data under the same experimental conditions. Although 52Mn offers a longer half-life and a multi gamma cascade enhancing ?+ + ? coincidences, but at the expense of higher background. In this study, we demonstrate that the applied selection criteria on the data measured with the modular J-PET can be used for PLI studies even with radionuclides with complex decay patterns.
Endorsing Titanium-Scandium Radionuclide Generator for PET and Positronium Imaging
P. Moskal, A. Khreptak, J. Choiński, P. Jones, I. Kadenko, A. Majkowska-Pilip, R. Palit, A. Stolarz, R. Walczak, E. Stępień
abstract
The development of PET and positronium imaging techniques is strictly related to the availability of suitable radionuclides and robust radiochemistry platforms. Among the emerging candidates, 44Sc has attracted significant interest due to its favourable physical properties, including a half-life of 4 hours, a pure emission profile, and the additional prompt -emission that enables advanced triple-photon detection schemes. These characteristics make 44Sc particularly promising for highresolution imaging and novel quantitative methodologies. However, routine clinical and preclinical implementation requires a practical, sustainable, and cost-efficient production route. In this context, we propose a titanium-scandium radionuclide generator as an optimal solution. This study focuses on optimising the synthesis of the long-lived parent isotope, 44Ti (T1/2 = 59.1 years), from which 44Sc can be selectively eluted in a chemically pure form when needed. An analysis of various production pathways was conducted, including proton and deuteron reactions on scandium, as well as alpha-particle and lithium-induced reactions on calcium, to determine the most efficient reaction parameters, target design, and expected yield. Furthermore, we identify some existing cyclotron facilities suitable for implementing this technology. Results indicate that efficient Ti production is achievable using proton beams in the 20-30 MeV range under extended irradiation conditions. The proposed generator system would enable routine and decentralised 44Sc supply. Its integration with the novel J-PET scanner may significantly reduce diagnostic costs and improve access to advanced PET imaging in regions with limited medical imaging infrastructure.
First Positronium Imaging Using 44Sc With the J-PET Scanner: a Case Study on the NEMA-Image Quality Phantom
Manish Das, Sushil Sharma, Ermias Yitayew Beyene, Aleksander Bilewicz, Jarosław Choiński, Neha Chug, Catalina Curceanu, Eryk Czerwiński, Kavya Valsan Eliyan, 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, Rafał Walczak, Ewa Ł. Stępień, Paweł Moskal
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 68Ga isotope. However, this isotope has limitations due to its comparatively low prompt gamma yields, which is crucial for positronium lifetime measurement. Among alternative radionuclides, 44Sc 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 44Sc, carried out on a NEMA-Image Quality (IQ) phantom using the Modular J-PET tomograph?the first plastic scintillators-based PET scanner.
Positronium Imaging: History, Current Status, and Future Perspectives
Paweł Moskal, Aleksander Bilewicz, Manish Das, Bangyan Huang, Aleksander Khreptak, Szymon Parzych, Jinyi Qi, Axel Rominger, Robert Seifert, Sushil Sharma, Kuangyu Shi, William Steinberger, Rafał Walczak, Ewa Stępień
abstract
Positronium imaging was recently proposed to image the properties of positronium atoms in the patient body. Positronium properties depend on the size of intramolecular voids and oxygen concentration; therefore, they deliver information different and complementary to the anatomic, morphological, and metabolic images. Thus far, the mean ortho-positronium lifetime imaging has been at the center of research interest. The first ex vivo and in vivo positronium lifetime images of humans have been demonstrated with the dedicated J-PET scanner enabling simultaneous registration of annihilation photons and prompt gamma from beta+gamma emitters. Annihilation photons are used to reconstruct the annihilation place and time while prompt gamma is used to reconstruct the time of positronium formation. This review describes recent achievements in the translation of positronium imaging into clinics. The first measurements of positronium lifetime in humans with commercial PET scanners modernized to register triple coincidences are reported. The in vivo observations of differences in ortho-positronium lifetime between tumor and healthy tissues and between different oxygen concentrations are discussed. So far, the positronium lifetime measurements in humans were completed with clinically available 68Ga, 82Rb, and 124I radionuclides. Status and challenges in developing positronium imaging on a way to a clinically useful procedure are presented and discussed.
Exploration of simultaneous dual-isotope imaging with multi-photon modular J-PET scanner
Ermias Yitayew Beyene, Manish Das, Martyna Durak-Kozica, Grzegorz Korcyl, Wiktor Mryka, Szymon Niedźwiecki, Szymon Parzych, Keyvan Tayefi Ardebili, Rafał Walczak, Kamil Wawrowicz, Ewa Stępień, Paweł Moskal
abstract
The modular J-PET scanner, comprising 24 compact and versatile modules, each consisting of 13 plastic strips with four SiPM detectors at the ends, represents a powerful tool for clinical applications in nuclear medical imaging. This study presents preliminary results from the exploration of simultaneous dual-isotope imaging using the modular J-PET system. Our approach involved two isotopes: 68Ge, characterized by a ringlike shape, and 22Na, exhibiting a point-like shape. The imaging was based on double-coincidence and triple-coincidence events. In the double coincidence case, both isotopes contributed comparably, whereas in the triple coincidence case 22Na dominated due to the prompt gamma being emitted with 100% of positron emissions, unlike 68Ga, where the prompt gamma was emitted in only 1.3% of cases after positron emission. In this work we present direct 2? images determined for two-signal events and images for three-signal events, with two signals from annihilation photons and one from a prompt gamma. These results showcase the preliminary findings from simultaneous dual-isotope imaging of 68Ga and 22Na isotopes using the modular J-PET scanner, which will be presented and discussed.
First Experimental Demonstration of Positronium Lifetime Imaging with 44Sc Using the J-PET Scanner
M. Das, S. Sharma, E. Y. Beyene, A. Bilewicz, J. Choiński, N. Chug, C. Curceanu, E. Czerwiński, J. Hajduga, S. Jalali, T. Kaplanoglu, Ł. Kapłon, K. Kasperska, A. Khreptak, G. Korcyl, K. Kubat, D. Kumar, A. Kunimmal Venadan, E. Lisowski, F. Lisowski, J. Mędrala-Sowa, S. Moyo, W. Mryka, S. Niedźwiecki, P. Pandey, S. Parzych, A. Porcelli, B. Rachwał, E. P.D. Río, M. Rädler, M. Skurzok, A. Stolarz, T. Szumlak, S. Tiwari, P. Tanty, K. Tayefi Ardebili, K. Valsan Eliyan, R. Walczak, E.Ł. Stępień, P. Moskal
published in: 2025 IEEE Nuclear Science Symposium (NSS), Medical Imaging Conference (MIC) and Room Temperature Semiconductor Detector Conference (RTSD)
Positronium lifetime imaging (PLI) [1], an extension of PET, provides insight into the submolecular properties of tissues by imaging the lifetime of the positronium atom [2]. Currently, the method is under rapid development as regards reconstruction [3], [4] and detection systems [5], [6]. The first studies with the J-PET scanner using 68Ga have demonstrated the feasibility of this technique in human subjects [6]. However, the Ga68 isotope has limitations due to its low yield of de-excitation photons necessary for positronium lifetime estimation. In this context, 44Sc emerges as a promising candidate for PLI [7], offering a clinically optimal half-life of 3.97 hours and a high deexcitation photon yield of 94.3 % with an energy of 1157 keV. In this work, we report the results of the successful demonstration of PLI with 44 Sc using the Modular J-PET tomograph, featuring triggerless data acquisition that enables simultaneous multiphoton detection [8]. 44Sc was produced at the Heavy Ion Laboratory in Warsaw and transported to Jagiellonian University in Kraków. A NEMA IQ phantom with six spheres was used. The three largest spheres were filled with 44Sc, and the three smallest with 18 F, both diluted with water, having an initial activity concentration ratio of 1:3. Event selection was based on the simultaneous detection of two 511 keV photons and one de-excitation photon, enabling reconstruction of images of the mean positronium lifetime [2], [6]. The measured mean o-Ps lifetime shows good agreement with previously reported values in water [9]. This study presents the first-ever demonstration of PLI with 44 Sc, marking a significant advancement and opening new possibilities for developing PLI for clinical applications.
First Experimental Demonstration of Positronium Lifetime Imaging with 44Sc Using the J-PET Scanner
M. Das, S. Sharma, E. Y. Beyene, A. Bilewicz, J. Choiński, N. Chug, C. Curceanu, E. Czerwiński, J. Hajduga, S. Jalali, T. Kaplanoglu, Ł. Kapłon, K. Kasperska, A. Khreptak, G. Korcyl, K. Kubat, D. Kumar, A. Kunimmal Venadan, E. Lisowski, F. Lisowski, J. Mędrala-Sowa, S. Moyo, W. Mryka, S. Niedźwiecki, P. Pandey, S. Parzych, A. Porcelli, B. Rachwał, E. P.D. Río, M. Rädler, M. Skurzok, A. Stolarz, T. Szumlak, S. Tiwari, P. Tanty, K. Tayefi Ardebili, K. Valsan Eliyan, R. Walczak, E.Ł. Stępień, P. Moskal
2025 IEEE Nuclear Science Symposium (NSS), Medical Imaging Conference (MIC) and Room Temperature Semiconductor Detector Conference (RTSD), Yokohama, Japan (1-8 November 2025))
Simulation studies of a brain PET insert for the total body J-PET tomograph
M. Rädler, E. Y. Beyene, A. Bilewicz, J. Choiński, N. Chug, C. Curceanu, E. Czerwiński, M. Das, J. Hajduga, S. Jalali, T. Kaplanoglu, Ł. Kapłon, A. Khreptak, G. Korcyl, K. Kubat, D. Kumar, A. Kunimmal Venadan, E. Lisowski, F. Lisowski, J. Mędrala-Sowa, S. Moyo, W. Mryka, S. Niedźwiecki, P. Pandey, S. Parzych, A. Porcelli, B. Rachwał, E. P. d. Río, S. Sharma, M. Skurzok, A. Stolarz, T. Szumlak, S. Tiwari, P. Tanty, K. Tayefi Ardebili, K. Valsan Eliyan, R. Walczak, E. Ł. Stępień, P. Moskal
IEEE NSS MIC RTSD in Yokohama
