MicroPET Peformance in the Presence of the Third Gamma

Document Type

Conference Proceeding

Publication Date



Physics and Astronomy


Isotopes in routine use for positron emission tomography (PET) produce only a single pair of 511 keV annihilation photons. "Dirty" positron emitters, e.g. 124I, that emit additional gammas are increasingly of interest. Performance of the Concorde microPET P4 small animal scanner was experimentally studied. Three phantoms were used to compare the pure positron emitter 18F to 124I and the convenient proxies 70As and 72As. While the third gamma had only a small impact on images of a contrast/detail phantom, resolution of hot sources on cold background was noticably reduced in a "Derenzo" phantom. A "NEMA" phantom exhibited a 15% background due to the third gamma.

Publication Title

Nuclear Science Symposium Conference Record, 2003 IEEE