title: EnPiT: filtered back-projection algorithm for helical CT using an n-Pi acquisition.
abstract: In this paper, we formulate a reconstruction algorithm for an n-Pi acquisition, where n can be any positive odd integer. The algorithm is a generalization of the method presented in (Bontus et al. 2003). It is based on the results obtained by Katsevich (2004). For the algorithm, different sets of filter-lines have to be defined. We describe the variation of these lines along the detector in some detail, before we discuss, how the method gives all Radon-plane contributions the correct weighting. The different sets of filter-lines are all contained within the n-Pi window, such that a practical realization is possible. Reconstruction results, which we present in the final section, show convincing image quality.
authors.affiliation: Philips Research Laboratories, Sector Technical Systems, Röntgenstrasse 24-26, D-22 335 Hamburg, Germany. claas.bontus@philips.com
authors.forename: Claas
authors.initials: C
authors.lastname: Bontus
authors.forename: Thomas
authors.initials: T
authors.lastname: Köhler
authors.forename: Roland
authors.initials: R
authors.lastname: Proksa
mesh_terms: D000465:Algorithms; D001185:Artificial Intelligence; D001921:Brain / Q000000981:diagnostic imaging*; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000379:methods*; D009716:Numerical Analysis, Computer-Assisted; D019047:Phantoms, Imaging; D011856:Radiographic Image Enhancement / Q000379:methods*; D011857:Radiographic Image Interpretation, Computer-Assisted / Q000379:methods*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012815:Signal Processing, Computer-Assisted; D036542:Tomography, Spiral Computed / Q000295:instrumentation / Q000379:methods*