Title :
A new cone beam reconstruction algorithm for the circular orbit
Author_Institution :
Appl. Sci. Lab., GE Med. Syst., Milwaukee, WI, USA
fDate :
30 Oct-5 Nov 1994
Abstract :
It is discovered by reformulating Grangeat´s algorithm that for the circular orbit, an arbitrary function to be reconstructed, f(r&oarr;), can be expressed as the sum of three terms: f(r&oarr;)=fM0(r&oarr;)+fM1(r&oarr;)+fN (r&oarr;), where fM0(r&oarr;) corresponds to the Feldkamp reconstruction, fM1(r&oarr;) represents the remaining part of the measurement space component of f(r&oarr;) that cannot be recovered by Feldkamp´s algorithm, and fN(r&oarr;) represents the null space component of f(r&oarr;). The discrepancy between this finding and the conventional wisdom is caused by the discontinuity of the redundancy function. Thus, a new cone beam reconstruction algorithm for the circular orbit is proposed as follows: 1) compute fM0(r&oarr;) using Feldkamp´s algorithm; 2) compute fM1(r&oarr;) using the formula developed here; and 3) estimate fN(r&oarr;) as suggested in Grangeat´s algorithm. By including the correction term fM1(r&oarr;), this new algorithm provides a more accurate reconstruction of the measurement space component of f(r&oarr;) than Feldkamp´s algorithm
Keywords :
computerised tomography; image reconstruction; medical image processing; Feldkamp reconstruction; Feldkamp´s algorithm; Grangeat´s algorithm; arbitrary function; circular orbit; cone beam reconstruction algorithm; measurement space component; medical diagnostic imaging; redundancy function; space component; Equations; Extraterrestrial measurements; Fault detection; Laboratories; Null space; Reconstruction algorithms; Redundancy; Regions; Sufficient conditions; Tomography;
Conference_Titel :
Nuclear Science Symposium and Medical Imaging Conference, 1994., 1994 IEEE Conference Record
Conference_Location :
Norfolk, VA
Print_ISBN :
0-7803-2544-3
DOI :
10.1109/NSSMIC.1994.474597
