3D attenuation correction for PET using uncollimated flood source transmission measurements

A method is presented for attenuation correction for The Queen's University 3-D PET (positron emission tomography) system using a flood source. Transmission data are coarsely binned into projections and the scatter contribution is subtracted. The emission data are not sorted into projections, so that these transmissions data are used to correct emission events at backprojection time either by direct calculation of the attenuation correction factors or by reconstruction of an attenuation image followed by reprojection. In this case, the latter method yields lower noise in the corrected emission image.<
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