Abstract：
:The purpose of this study was to improve the performance of a small gamma camera, utilizing a NaI(Tl) plate and a 5" position sensitive PMT. We attempted to build a NaI(Tl) plate crystal system which retained all its advantages, while at the same time integrating some of the advantages inherent in an array-type scintillation crystal system. Flood images were obtained with a lead hole mask, and position mapping was performed by detecting hole positions in the flood image. Energy calibration was performed using the energy spectra obtained from each hole position. Flood correction was performed using a uniformity correction table containing the relative efficiency of each image element. The spatial resolution was improved about 16% after correction at the centre field of view. Resolution deterioration at the outer field of view (OFOV) was considerably ameliorated, from 6.7 mm to 3.2 mm after correction. The sensitivity at the OFOV was also increased after correction, from 0.7 cps microCi(-1) to 2.0 cps microCi(-1). The correction also improved uniformity, from 5.2% to 2.1%, and linearity, from 0.5 mm to 0 mm. The results of this study indicate that the revised correction method can be employed to considerably improve the performance of a small gamma camera using a NaI(Tl) plate-type crystal. This method also provides high spatial resolution and linearity, like array-type crystals do, while retaining the specific advantages of plate-type crystals.
journal_name
Phys Med Bioljournal_title
Physics in medicine and biologyauthors
Jeong MH,Choi Y,Chung YH,Song TY,Jung JH,Hong KJ,Min BJ,Choe YS,Lee KH,Kim BTdoi
10.1088/0031-9155/49/21/008subject
Has Abstractpub_date
2004-11-07 00:00:00pages
4961-70issue
21eissn
0031-9155issn
1361-6560journal_volume
49pub_type
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