Investigation of gamma camera detector uniformity using a dynamic line phantom.
BACKGROUND
Investigation of the applicability of the dynamic line phantom for determination o the uniformity of circular and rectangular field-of-view gamma cameras.


METHODS
Count rate - activity and uniformity - count rate functions were determined by the dynamic line phantom on three circular field-of-view gamma cameras with 37 PMTs, on one circular field of view camera with 19 PMTs, and on one rectangular field-of view gamma camera with 59 PMTs, with and without a collimator. For an evaluation of the efficacy of the dynamic line phantom, the results were compared with the uniformity values obtained with a 99mTc point source and a 57-Co sheet source.


RESULTS
In the optimum count rate range (20,000-30,000 cps for a circular field-of-view, 15,000-65,000 cps for a rectangular field-of-view) determined individually for each gamma camera, the uniformity values obtained with the dynamic line phantom did not differ statistically from the refined with the 99mTc point source or the 57-Co sheet source.


CONCLUSIONS
The dynamic line phantom is suitable for the determination of detector uniformity, but the measurements should be performed within a well-defined activity (count rate) interval.
Department of Nuclear Medicine, Albert Szent-Györgyi Medical University of Szeged, Hungary. serat@comser.szote.u-szeged.hu
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Séra
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Mester
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Csernay
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Pávics