|
KMID : 1144120110010030174
|
|
Biomedical Engineering Letters
2011 Volume.1 No. 3 p.174 ~ p.174
|
|
|
Evaluation of a fast photomultiplier tube for time-of-flight PET
|
|
Lee Jin-Pyo
Ito Mikiko
Lee Jae-Sung
|
|
|
Abstract
|
|
|
Purpose: Adding time-of-flight (TOF) information to positron emission tomography (PET) can lead to an improvement in image quality because TOF information allows the estimation of gamma ray annihilation positions in three dimensions. For accurate position estimation, precise time resolution is the most important characteristic required of TOF-PET detectors. The aims of this study were to establish the optimal setup for timing measurements and to evaluate the timing performance of a fast photomultiplier tube (PMT) (Hamamatsu R9800) coupled with a lutetium yttrium orthosilicate (LYSO) scintillation crystal for TOF-PET detector development.
Methods: Performance of a fast PMT (diameter, 25 mm; length, 55 mm) coupled with a LYSO crystal (4 × 4 × 10 mm3) was measured in coincidence experiments with 511 keV annihilation photons from a 22Na gamma source. Timing measurement optimization was carried out with a leading-edge discriminator (LED) and a constant fraction discriminator (CFD).
Results: Results showed the optimal timing resolution could be obtained with a CFD time delay of 1 ns; timing resolutions (FWHM) of the LYSO crystal-coupled fast PMT were measured to be 198 and 254 ps for two different R9800 PMTs. The energy resolutions at 511 keV were 10.8% and 10.6%, respectively. Additional experiments to determine the position uncertainty were performed at three different source positions and the position uncertainty (FWHM) in the TOF measurement using these PMTs was estimated to be 4.50 cm.
Conclusions: The performance of fast R9800 PMT coupled with a LYSO crystal showed good potential for development as a TOF-PET detector module.
|
|
|
KEYWORD
|
|
|
Positron emission tomography (PET), Time-of-flight, Fast PMT, Timing resolution, Nuclear medicine
|
|
|
FullTexts / Linksout information
|
|
|
|
|
Listed journal information
|
|
|
|