Assessment of Gamma Camera Performance in Nuclear Medicine Departments Khartoum

Abstract

This study was performed to evaluate the gamma camera machine performance in nuclear medicine at Alneelain Medical Center (NMDC) for the following parameters: Energy Resolution, Uniformity, center of rotation and sensitivity by using 99mTC. We found about the center of rotation, the deviation of gantry rotation (0.1 mm) ,and the average deviation could be as 0.14 mm. such deviation is within the tolerance level of gamma camera performance, and this period the gantry rotation started to deviate from the normal at 90o to reach about 0.4 mm at 135o i.e. at the 3rd. quadrant and by 180o the deviation approaching to 0.8 mm. and from 180 up to 360o the deviation fluctuated between 1.0 to 1.3 mm which is still within the tolerance level of system working. The results reveal that the energy resolution showed a central peak of energy at 140 KVp and the limit of the window for the energy about 7.5% (10.5). The average of FWHM was about 10.35 and the stander deviation was about 2.6 which were all within the standard levels. Also the result showed that the Differential Uniformity UFOV, CFOV in the practical about 2.78%, 2.04% which were within the acceptable limit, as well as Integral Uniformity, UFOV, and CFOV in the practical about 5.07%, 3.1%. Also the result showed that The Average of sensitivity around 77.23 and the drop of peak of the sensitivity according to the leakage of the current and the decay of the end of the below carve according to the dead time.