title: Incremental beamwise backprojection using geometrical symmetries for 3D PET reconstruction in a cylindrical scanner geometry.
abstract: Cho et al have proposed a fast backprojection scheme for parallel beam geometries, the incremental algorithm, which performs backprojection on a ray-by-ray (beam-by-beam) basis as opposed to a pixel-by-pixel approach. We present an extension of this incremental, beamwise, backprojection algorithm to the case of volume reconstruction of data acquired by a cylindrical, multiring positron tomograph. Use is made of geometrical symmetries of the image volume. This method results in a twelve-fold reduction of execution time compared with a straightforward, voxel-driven implementation of the same interpolation equations.
authors.affiliation: Institute of Nuclear Physics, University of Lausanne, Switzerland.
authors.forename: M L
authors.initials: ML
authors.lastname: Egger
authors.forename: C
authors.initials: C
authors.lastname: Joseph
authors.forename: C
authors.initials: C
authors.lastname: Morel
mesh_terms: D000465:Algorithms; D003952:Diagnostic Imaging / Q000379:methods; D014055:Tomography, Emission-Computed / Q000379:methods*