Title :
Using opposite rays to detect organ motion in CT images
Author :
Linney, N.C. ; Gregson, P.H.
Author_Institution :
Dept. of Electr. & Comput. Eng., DalTech, Halifax, NS, Canada
Abstract :
Motion artifacts have been identified as a problem in medical tomography systems. This paper describes an approach that isolates the motion in CT images. Using a fan-beam projection system with one source and equiangular rays, the algorithm combines information from projections that are opposite in space and separated in time to isolate and identify motion. The algorithm was evaluated using the Shepp-Logan (1974) phantom in which one of the interior elements was made to move in a physiologically relevant manner. A sinogram of differences was created and from this an image of the moving phantom element was reconstructed using a standard filtered backprojection reconstruction algorithm. A standard hardware configuration was simulated. The motion was isolated in the sinogram domain and an image of the moving phantom element was reconstructed with little error
Keywords :
computerised tomography; diagnostic radiography; image motion analysis; image reconstruction; image sampling; medical image processing; CT images; Shepp-Logan phantom; algorithm; equiangular rays; fan-beam projection system; filtered backprojection reconstruction algorithm; interior elements; medical X-ray CT systems; medical tomography systems; motion artifacts; motion isolation; opposite rays; organ motion detection; phantom element reconstruction; sampling errors; simulation; sinogram; spatio-temporal uncertainty; standard hardware configuration; Biomedical imaging; Computed tomography; Geometry; Hardware; Image reconstruction; Imaging phantoms; Motion detection; Reconstruction algorithms; Signal processing algorithms; Uncertainty;
Conference_Titel :
Electrical and Computer Engineering, 2000 Canadian Conference on
Conference_Location :
Halifax, NS
Print_ISBN :
0-7803-5957-7
DOI :
10.1109/CCECE.2000.849756
