By Topic

Exact Radon rebinning algorithm for the long object problem in helical cone-beam CT

Sign In

Cookies must be enabled to login.After enabling cookies , please use refresh or reload or ctrl+f5 on the browser for the login options.

Formats Non-Member Member
$31 $13
Learn how you can qualify for the best price for this item!
Become an IEEE Member or Subscribe to
IEEE Xplore for exclusive pricing!
close button

puzzle piece

IEEE membership options for an individual and IEEE Xplore subscriptions for an organization offer the most affordable access to essential journal articles, conference papers, standards, eBooks, and eLearning courses.

Learn more about:

IEEE membership

IEEE Xplore subscriptions

6 Author(s)
Schaller, S. ; Siemens Med. Tech., Forchheim, Germany ; Noo, F. ; Sauer, F. ; Tam, K.C.
more authors

This paper addresses the long object problem in helical cone-beam computed tomography. The authors present the PHI-method, a new algorithm for the exact reconstruction of a region-of-interest (ROI) of a long object from axially truncated data extending only slightly beyond the ROI. The PHI-method is an extension of the Radon-method, published by Kudo et al. in Phys. in Med. and Biol., vol. 43, p. 2885-909 (1998). The key novelty of the PHI-method is the introduction of a virtual object f φ(x) for each value of the azimuthal angle φ in the image space, with each virtual object having the property of being equal to the true object f(x) in some ROI Ω m. The authors show that, for each φ, one can calculate exact Radon data corresponding to the two-dimensional (2-D) parallel-beam projection of f φ(x) onto the meridian plane of angle φ. Given an angular range of length π of such parallel-beam projections, the ROI Ω m can be exactly reconstructed because f(x) is identical to f φ(x) in Ω m. Simulation results are given for both the Radon-method and the PHI-method indicating that (1) for the case of short objects, the Radon- and PHI-methods produce comparable image quality, (2) for the case of long objects, the PHI-method delivers the same image quality as in the short object case, while the Radon-method fails, and (3) the image quality produced by the PHI-method is similar for a large range of pitch values.

Published in:

Medical Imaging, IEEE Transactions on  (Volume:19 ,  Issue: 5 )