Implementation and evaluation of a calculated attenuation correction for PET

A highly reliable and consistent method for automated calculated attenuation correction for PET (positron emission tomography) was developed. The method was tested in nearly 300 brain studies and shown to accurately find the object outline, regardless of the tracer used and the activity distribution. The Bergstrom method of determining the contour of a convex object from its emission projection sinogram was implemented to eliminate the initial reconstruction and ellipse drawing steps. The efficacy of this method is highly dependent on a robust algorithm for determining the border between the activity uptake and scatter background. An effective, tracer-distribution-independent, edge detection algorithm is presented that has primarily been applied to brain studies using a variety of tracers (/sup 15/O-H/sub 2/O, /sup 18/F-FGD, /sup 18/F-FDOPA), in extreme uptake distributions, and tested on three different PET systems. The algorithm has also been extended for abdominal PET scans and tested in a limited series of kidney flow studies using /sup 13/N-NH/sub 3/.<>