Abstract:
:The silicon photomultiplier (Si-PM) is a promising photo-detector for PET for use in magnetic resonance imaging (MRI) systems because it has high gain and is insensitive to static magnetic fields. Recently we developed a Si-PM-based depth-of-interaction PET system for small animals and performed simultaneous measurements by combining the Si-PM-based PET and the 0.15 T permanent MRI to test the interferences between the Si-PM-based PET and an MRI. When the Si-PM was inside the MRI and installed around the radio frequency (RF) coil of the MRI, significant noise from the RF sequence of the MRI was observed in the analog signals of the PET detectors. However, we did not observe any artifacts in the PET images; fluctuation increased in the count rate of the Si-PM-based PET system. On the MRI side, there was significant degradation of the signal-to-noise ratio (S/N) in the MRI images compared with those without PET. By applying noise reduction procedures, the degradation of the S/N was reduced. With this condition, simultaneous measurements of a rat brain using a Si-PM-based PET and an MRI were made with some degradation in the MRI images. We conclude that simultaneous measurements are possible using Si-PM-based PET and MRI.
journal_name
Phys Med Bioljournal_title
Physics in medicine and biologyauthors
Yamamoto S,Watabe T,Watabe H,Aoki M,Sugiyama E,Imaizumi M,Kanai Y,Shimosegawa E,Hatazawa Jdoi
10.1088/0031-9155/57/2/N1subject
Has Abstractpub_date
2012-01-21 00:00:00pages
N1-13issue
2eissn
0031-9155issn
1361-6560journal_volume
57pub_type
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