Abstract:
:A Geiger-mode avalanche photodiode (Si-PM) is a promising photodetector for PET, especially for use in a magnetic resonance imaging (MRI) system, because it has high gain and is less sensitive to a static magnetic field. We developed a Si-PM-based depth-of-interaction (DOI) PET system for small animals. Hamamatsu 4 × 4 Si-PM arrays (S11065-025P) were used for its detector blocks. Two types of LGSO scintillator of 0.75 mol% Ce (decay time: ∼45 ns; 1.1 mm × 1.2 mm × 5 mm) and 0.025 mol% Ce (decay time: ∼31 ns; 1.1 mm × 1.2 mm × 6 mm) were optically coupled in the DOI direction to form a DOI detector, arranged in a 11 × 9 matrix, and optically coupled to the Si-PM array. Pulse shape analysis was used for the DOI detection of these two types of LGSOs. Sixteen detector blocks were arranged in a 68 mm diameter ring to form the PET system. Spatial resolution was 1.6 mm FWHM and sensitivity was 0.6% at the center of the field of view. High-resolution mouse and rat images were successfully obtained using the PET system. We confirmed that the developed Si-PM-based PET system is promising for molecular imaging research.
journal_name
Phys Med Bioljournal_title
Physics in medicine and biologyauthors
Yamamoto S,Imaizumi M,Watabe T,Watabe H,Kanai Y,Shimosegawa E,Hatazawa Jdoi
10.1088/0031-9155/55/19/013subject
Has Abstractpub_date
2010-10-07 00:00:00pages
5817-31issue
19eissn
0031-9155issn
1361-6560pii
S0031-9155(10)60352-1journal_volume
55pub_type
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