Comparison of Six Attenuation Correction Schemes in Clinical Cerebral 3d Positron Emission Tomography

The aim of this study is to compare the effect of the two major classes of methods used to determine the attenuation map, i.e. non-uniform versus uniform, on 3D brain PET clinical studies based on qualitative assessment as well as absolute and relative quantitative volume of interest (VOI)based analysis. The results revealed statistically significant differences between the six attenuation correction methods. It was concluded that non-uniform attenuation correction is the gold standard for quantitative 3D PET. It should, however, be recognised that methods, which do not require a transmission scan, allow to reduce patient scanning time, increase scanner throughput and avoid misalignment between emission and pre-injection transmission scanning. To this end, derivation of the attenuation map from already acquired magnetic resonance images looks promising.