Optimum Energy Window In Liver Scintigraphy
Alireza Sadremomtaz, Mohaddeseh Saber Zidehsaraei
Keywords: energy window, image quality, noise, SIMIND, simulation.
Abstract: In liver scintigraphy, radioactive tracers, in addition to liver, are accumulated in other organs such as spleen. It leads to the presence of secondary source, which affects image quality. Therefore, knowing the influence of the noise arising from the secondary source and trying to reduce the additional data is necessary. In nuclear medicine imaging, using of energy window is a useful way to reduce the noise. In this paper, we try to find an optimum energy window to reduce the noise for two different low energy collimators. Liver scintigraphy images with and without activity in spleen were simulated by SIMIND software with different energy window percentages and with Low-Energy High-Resolution (LEHR) and Low-Energy General-Purpose (LEGP) collimators. We used with activity of 190 MBq. Spleen was outside of the camera field of view so that just its noise effects on the liver image is examined. Finally, the images of liver with activity in spleen were compared with that without activity in spleen by MATLAB code.
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