Title :
Determination of both mechanical and electronic shifts in cone beam SPECT
Author :
Li, J. ; Jaszczak, R.J. ; Wang, H. ; Greer, K.L. ; Coleman, R.E.
Author_Institution :
Radiol. Dept., Duke Univ. Med. Center, Durham, NC, USA
Abstract :
The difference between the displacement of the center-of-rotation (mechanical shift) and the electronic centering misalignment (electronic shift) in cone beam single photon emission computed tomography (SPECT) is evaluated. A method is proposed to determine both mechanical shift (MS) and electronic shift (ES) using the coordinate of the centroid of a projected point source sampled over 360° and the Marquardt nonlinear fitting algorithm. Both shifts are characterized by two orthogonal components. This method is verified using Monte Carlo simulated point source data with different combinations of mechanical and electronic shifts. Both shifts can be determined precisely. This method is also applied to a CB-SPECT system. This study suggests that calibration of the system is needed on a periodic basis
Keywords :
biomedical electronics; computerised tomography; radioisotope scanning and imaging; Marquardt nonlinear fitting algorithm; Monte Carlo simulated data; centre-of-rotation displacement; centroid coordinate; cone beam SPECT; electronic centering misalignment; electronic shift; mechanical shift; medical diagnostic imaging; nuclear medicine; orthogonal components; periodic system calibration; projected point source; single photon emission computed tomography; Calibration; Cancer; Collimators; Geometry; Image resolution; Monte Carlo methods; Object detection; Radiology; Tomography;
Conference_Titel :
Nuclear Science Symposium and Medical Imaging Conference, 1992., Conference Record of the 1992 IEEE
Conference_Location :
Orlando, FL
Print_ISBN :
0-7803-0884-0
DOI :
10.1109/NSSMIC.1992.301476
