Positron emission tomography imaging harnessing polarization correlations

5 Dec 2025, 09:30
30m
Institute of Physics, Bijenička 46

Institute of Physics, Bijenička 46

Speaker

Prof. Mihael Makek (Department of Physics, Faculty of Science, University of Zagreb)

Description

Conventional Positron Emission Tomography (PET) imaging is based on measurement of energy and coincidence time of back-to-back photons from positron annihilation. The annihilation quanta posses yet another correlation - the orthogonality of their initial polarizations. We developed a demonstrator based on single-layer Compton polarimeters to study the potential of this additional information to enhance PET. We present the imaging tests done with two Ge-68 rod sources of 45 MBq each, and with NEMA NU-4 phantom with a Ga-68 solution of 400 MBq initial activity. To assess the performance we compare the images reconstructed using polarization-correlated Compton events with single-pixel gamma identification, as a reference. We observed the spatial resolutions of from 4.3±0.3 mm to 6.3±0.3 mm, in the former case, and 2.5±0.3 mm in the latter. We also show that ∼10% sensitivity increase can be obtained by combining all events.

Authors

Prof. Mihael Makek (Department of Physics, Faculty of Science, University of Zagreb) Ana Marija Kožuljević (Institute for Medical Research and Occupational Health) tomislav bokulic (Department of physics, Faculty of Science, University of Zagreb) Darko Grošev (University Hospital Centre Zagreb) Dr Siddharth Parashari (Instituto de Física Corpuscular (IFIC)) Luka Pavelić (Institute for Medical Research and Occupational Health) Marijan Žuvić (University Hospital Centre Zagreb)

Presentation materials