Assessment of OSEM & FBP Reconstruction Techniques in Single Photon Emission Computed Tomography Using SPECT Phantom as Applied on Bone Scintigraphy

Filtered back projection (FBP) method and maximum likelihood expection maximization (OSEM) method are currently used for reconstruction of SPECT images in clinical studies. The aim of this work is to compare the image quality using different reconstruction techniques of a SPECT phantom as applied to bone scintigraphy. The resolution and contrast of the hot spheres were observed using a phantom insert with OSEM and FBP techniques. The activity profile, drown through the hot spheres demonstrates that the FBP image is often blurred and more noisy than the image which reconstructed iteratively using OSEM. This means that there is an improvement in resolution of the image with OSEM reconstruction technique. There is a decreasing in counts of reconstructed slices by FBP technique and increase in counts of the same reconstructed slices by OSEM technique. This shows an improvement in image quality and increased accuracy of the OSEM, technique to its algorithm accuracy. Thus OSEM can replace the FBP technique for its merits.