Basic performance evaluation of a Si-PM array-based LGSO phoswich DOI block detector for a high-resolution small
1Department of Radiological and Medical Laboratory Sciences, Nagoya University, Graduate School of Medicine, 1-1-20 Daiko-Minami, Higashi-ku, Nagoya 461-8673, Japan. s-yama@met.nagoya-u.ac.jp
Radiological Physics and Technology
|December 29, 2012
Summary
Silicon photomultiplier (Si-PM) arrays coupled with scintillators of varying decay times demonstrate potential for depth-of-interaction (DOI) detection. This technology shows promise for high-resolution positron emission tomography (PET) systems.
Area of Science:
- Nuclear Instrumentation
- Medical Physics
- Materials Science
Background:
- Silicon photomultipliers (Si-PMs) are advanced photodetectors with potential applications in Positron Emission Tomography (PET).
- The feasibility of using Si-PMs for Depth-of-Interaction (DOI) detection via scintillator decay time differences and pulse shape analysis remains underexplored.
Purpose of the Study:
- To investigate the efficacy of Si-PM arrays for developing DOI block detectors using pulse shape analysis.
- To evaluate the performance of Si-PMs with scintillators exhibiting distinct decay times for high-resolution PET applications.
Main Methods:
- Utilized a Hamamatsu 4x4 Si-PM array (S11065-025P) coupled with Ce-doped Gadolinium Silicon Oxide (GSO) and Lutetium Gadolinium Silicon Oxide (LGSO) scintillators.
- Measured energy resolution and gain variations with GSO scintillators; tested LGSO scintillators with different decay times (~31 ns and ~46 ns) for DOI capability.
- Employed pulse shape analysis to assess DOI performance, analyzing peak-to-valley ratios and spatial resolution.
Main Results:
- Achieved an energy resolution of 18 ± 4.4% FWHM for a Cs-137 source using the Si-PM array-based GSO detector.
- Demonstrated clear resolution of sub-millimeter crystals in the position map of the LGSO DOI block detector.
- Obtained a peak-to-valley ratio of 2.2 from pulse shape spectra for the LGSO DOI block detector.
Conclusions:
- Si-PM array-based DOI block detectors are a promising technology for advancing high-resolution small animal PET systems.
- The study confirms the viability of using pulse shape analysis with scintillators of differing decay times for accurate DOI measurement.
