Local threshold for segmented attenuation correction of PET imaging of the thorax

Local threshold for segmented attenuation correction technique has been developed for positron emission tomography using short (2-3 minutes) post-injection transmission scans. The technique implements an optimal threshold method on localized histograms to get pseudo-anatomic segmentation on transmission images. Theoretical values of attenuation coefficient are assigned to correspondent anatomic regions. Emission images are reconstructed using attenuation correction factors computed by forward-projecting segmented transmission images. Phantoms and clinical cardiac images are studied using this technique. The technique has been found linearly correlated with the standard method (15 minutes, pre-injection transmission scans), reducing noise in the final emission Images, eliminating process for substraction emission data from transmission scan, cutting down scan time and increasing patient throughput