Title :
A new approximate algorithm for image reconstruction in cone-beam spiral CT at small cone-angles
Author :
Schaller, Stefan ; Flohr, Thomas ; Steffen, Peter
Author_Institution :
Telecommun. Inst., Erlangen-Nurnberg Univ., Germany
Abstract :
Presents a new approximate algorithm for image reconstruction with cone-beam spiral CT data at relatively small cone-angles. Based on the algorithm of Wang et al. (1993), our method combines a special complementary interpolation with filtered backprojection. The presented algorithm has three main advantages over Wang´s algorithm: (1) It overcomes the pitch limitation of Wang´s algorithm. (2) It significantly improves z-resolution when suitable sampling schemes are applied. (3) It avoids the waste of applied radiation dose inherent to Wang´s algorithm. Usage of the total applied dose is an important requirement in medical imaging. Our method has been implemented on a standard workstation. Reconstructions of computer-simulated data of different phantoms, assuming sampling conditions and image quality requirements typical to medical CT, show encouraging results
Keywords :
computerised tomography; dosimetry; filtering theory; image reconstruction; image resolution; image sampling; interpolation; medical image processing; applied radiation dose; approximate algorithm; computer-simulated data; cone-beam spiral CT; filtered backprojection; image quality; image reconstruction; medical CT; medical imaging; phantoms; pitch limitation; sampling schemes; small cone-angles; special complementary interpolation; standard workstation; z-resolution; Biomedical imaging; Computed tomography; Extraterrestrial measurements; Image reconstruction; Orbits; Reconstruction algorithms; Sensor arrays; Spirals; X-ray detection; X-ray detectors;
Conference_Titel :
Nuclear Science Symposium, 1996. Conference Record., 1996 IEEE
Conference_Location :
Anaheim, CA
Print_ISBN :
0-7803-3534-1
DOI :
10.1109/NSSMIC.1996.587959
