Assessment of Gamma Camera SPECT Resolution using Developed Quality Control Phantom

Abstract

The aim of this study; was to developed and designs an indigenous quality control phantom QCP to be used for gamma camera resolution QC test which installed at Royal Care hospital (RCH) and Radiation & Isotopes Center of Khartoum (RICK), as well to compare its performance relative to the standard QC phantom recommended by National Electronic Manufacture Association NEMA. The phantom has been designed based on the parameters and specifications recommended by NEMA with specific indigenous designing in view of utilizing local cheep material such as Perspex and wires lead and geometrical engineering. The comparative QC assessment for RCH and RICK revealed that: for RCH and RICK the resolution was 94.0% and 89.5% respectively which was dependant on the minimum object size resolved in the designed phantom (0.5 mm), while the resolution obtained by NEMA standard phantom showed 95.5% and 91.8% respectively. Quite similar resolution% has been obtained by the designed phantom depending on the object frequency (number of object/cm) i.e. number of lead wires resolved per cm2

, in this view the resolution was resolution was 94% and 90.3% respectively and in comparison with that obtained by NEMA phantom which was 95.5% and 91.8% respectively, the average deviation factor of the designed phantom from the standard was 1.5% - 1.9. Also the general trend of correlation between object size versus resolution showed a linear proportional equation in a form of y = 6.59x + 47.87 and y = 6.64x + 43.1 for RCH and RICK respectively with significant correlation as R2

= 0.98. And for object frequency versus resolution, the equation trend was inversely according to: for RCH and for RICK, where x refers to object frequency and y refers to resolution%, with significant correlation as R2 = 1.