Abstract:
This study was designed to experiment the result of the indigenous phantom with associated
algorism and compares the result to the standard one. The phantom was designed according to
the parameters recommended by NEMA, IAEA and some other researcher. A low cost material
were used to simulate the 4-quadrate bar phantom, Slit phantom and Liquid flood phantom in
order to achieve the gamma camera resolution, linearity and uniformity. A Perspex materials was
used to fabricate the flood phantom and Perspex with a lead materials and silicon were used to
simulate the bar phantom while a pure lead was used to fabricate the Slit phantom. IDL was used
to develop a mathematical algorism in order to analysis the result of indigenous phantom. The
devolved phantom was experimented at Royal Care Hospital RCH and Radiation and Isotopes
Center of Khartoum RICK. 1.3mCi of
99m
Tc and 1500ml water were used to prepare the flood
phantom and then is centered at camera table with four quadrant bar phantom or Slit phantom
perpendicular to it and image were acquired with optimum matrix size. Then the images were
assessed using our developed IDL algorism to measure the resolution, linearity and uniformity of
those cameras. The results of the fabricated phantom showed that the resolution of two cameras
increase as the objects size increased and the camera resolution decreased as the object
frequencies increased with averaged resolution of 94% and 89.5% with comparison to standard
NEMA phantom which represent resolution of 95.5% and 90.8% for RCH and RCIH
respectively. The spatial linearity is calculated and was 0631mm and 0.639mm for X and Y axis
respectively for UFOV and the slandered phantom appear an absolute linearity of 0.70mm for
both axis. The uniformity of the two cameras showed a 3.18% and 2.27% for I.U and D.U
respectively for UFOV and the standard phantom shows uniformity of 2.0% and 1.5% for I.U
and D.U for UFOV respectively. The developed phantom could be used with acceptable
accuracy in the field of nuclear medicine to curry out the quality control tests of gamma camera
SPECT, which is consider as general multi functional phantom as it could measures the
resolution, linearity and flood field uniformity independency on type or manufactures of camera.
