ABSTRACT
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.
