Scintillator selection for MR compatible gamma detectors

We investigated magnetic susceptibility of several scintillators in order to select the best material for MR compatible gamma detectors. The scintillators investigated were NaI(Tl) in Al container, NaI(Tl) in Cu container, CsI(Tl), BGO, LSO, LGSO, and GSO. NaI(Tl) in Al container, NaI(Tl) in Cu container and CsI(Tl) are candidates for an MR compatible gamma probe, imaging probe or SPECT, while BGO, LSO, LGSO, and GSO are the candidates for MR compatible PET. We also investigated image artifact and distortion by scanning these scintillators by an MRI. Susceptibility of NaI(Tl), CsI(Tl), BGO, and LSO showed similar to human tissue. In these scintillators, NaI(Tl) in Cu container showed the nearest susceptibility to human tissue and smallest artifact on the MRI image and is a good material for an MR compatible gamma probe or imaging probe as well as SPECT. For an MR compatible PET, BGO and LSO showed similar susceptibility to human tissue and small artifacts on the MRI images. However LGSO and GSO showed much different susceptibility from human tissue and produced significant artifact and distortion on the MRI images because of the gadolinium (Gd) in these scintillators.