Nuclear medical imaging using β +γ coincidences from 44Sc radio-nuclide with liquid xenon as detection medium

• Published in: Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment Vol. 571; no. 1; pp. 142 - 145
• Main Authors: Grignon, C., Barbet, J., Bardiès, M., Carlier, T., Chatal, J.F., Couturier, O., Cussonneau, J.P., Faivre, A., Ferrer, L., Girault, S., Haruyama, T., Le Ray, P., Luquin, L., Lupone, S., Métivier, V., Morteau, E., Servagent, N., Thers, D.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01-02-2007
• Subjects: Liquid xenon; Medical imaging; Scandium; 77.22.−d; Liquid xenon; 29.40.Mc; 87.58.Fg; Medical imaging; Scandium; 95.55.Ka
• ISSN: 0168-9002; 1872-9576
• DOI: 10.1016/j.nima.2006.10.048

We report on a new nuclear medical imaging technique based on the measurement of the emitter location in the three dimensions with a few mm spatial resolution using β
+γ emitters. Such measurement could be realized thanks to a new kind of radio-nuclides which emit a γ-ray quasi-simultaneously with the β
+ decay. The most interesting radio-nuclide candidate, namely
44Sc, will be potentially produced at the Nantes cyclotron ARRONAX. The principle is to reconstruct the intersection of the classical line of response (obtained with a standard PET camera) with the direction cone defined by the third γ-ray. The emission angle measurement of this additional γ-ray involves the use of a Compton telescope for which a new generation of camera based on a liquid xenon (LXe) time projection chamber is considered. GEANT3 simulations of a large acceptance LXe Compton telescope combined with a commercial micro-PET (LSO crystals) have been performed and the obtained results will be presented. They demonstrate that a good image can be obtained from the accumulation of each three-dimensional measured position. A spatial resolution of 2.3
mm has been reached with an injected activity of 0.5
MBq for a
44Sc point source emitter.