Title :
Helical-scan computed tomography using cone-beam projections
Author :
Kudo, Hiroyuki ; Saito, Tsuneo
Author_Institution :
Dept. of Electr. Commun., Tohoku Univ., Sendai, Japan
Abstract :
A fast data-acquisition method for 3-D X-ray computed tomography is proposed. The method continuously rotates a cone-beam X-ray source and a 2-D detector constructed by stacking 1-D circular detector arrays for the fan-beam computed tomography. Simultaneously, a patient is translated in the field of view of the X-ray source. This method is called helical-san, because it provides cone-beam projections measured by moving an X-ray source on a helix surrounding the patient. An approximate convolution backprojection image reconstruction algorithm for the helical-scan is developed by extending L.A. Feldkamp´s (1984) cone-beam reconstruction algorithm, for the circular-scan. How one should choose geometrical parameters of the data-acquisition system is discussed. Furthermore, the performance of the proposed method is analyzed by evaluating the point spread function of the reconstruction algorithm.<>
Keywords :
computerised tomography; data acquisition; 2D detector; 3D X-ray CT; cone-beam projections; convolution backprojection image reconstruction algorithm; geometrical parameters; helical-scan computed tomography; medical diagnostic imaging; point spread function; reconstruction algorithm; Computed tomography; Convolution; Image reconstruction; Performance analysis; Reconstruction algorithms; Sensor arrays; Stacking; X-ray detection; X-ray detectors; X-ray imaging;
Conference_Titel :
Nuclear Science Symposium and Medical Imaging Conference, 1991., Conference Record of the 1991 IEEE
Conference_Location :
Santa Fe, NM, USA
Print_ISBN :
0-7803-0513-2
DOI :
10.1109/NSSMIC.1991.259259
