Document Type
Conference Proceeding
Language
eng
Format of Original
10 p.
Publication Date
5-2004
Publisher
Society of Photo-Optical Instrumentation Engineers
Source Publication
SPIE Proceedings: Medical Imaging: Physics of Medical Imaging
Source ISSN
2329-4302
Original Item ID
doi: 10.1117/12.536032
Abstract
An inverse-geometry volumetric CT (IGCT) system for imaging in a single fast rotation without cone-beam artifacts is being developed. It employs a large scanned source array and a smaller detector array. For a single-source/single-detector implementation, the FOV is limited to a fraction of the source size. Here we explore options to increase the FOV without increasing the source size by using multiple detectors spaced apart laterally to increase the range of radial distances sampled. We also look at multiple source array systems for faster scans. To properly reconstruct the FOV, Radon space must be sufficiently covered and sampled in a uniform manner. Optimal placement of the detectors relative to the source was determined analytically given system constraints (5cm detector width, 25cm source width, 45cm source-to-isocenter distance). For a 1x3 system (three detectors per source) detector spacing (DS) was 18deg and source-to-detector distances (SDD) were 113, 100 and 113cm to provide optimum Radon sampling and a FOV of 44cm. For multiple-source systems, maximum angular spacing between sources cannot exceed 125deg since detectors corresponding to one source cannot be occluded by a second source. Therefore, for 2x3 and 3x3 systems using the above DS and SDD, optimum spacing between sources is 115deg and 61deg respectively, requiring minimum scan rotations of 115deg and 107deg. Also, a 3x3 system can be much faster for full 360deg dataset scans than a 2x3 system (120deg vs. 245deg). We found that a significantly increased FOV can be achieved while maintaining uniform radial sampling as well as a substantial reduction in scan time using several different geometries. Further multi-parameter optimization is underway.
Recommended Citation
Mazin, Samuel R.; Schmidt, Taly Gilat; Solomon, Edward G.; Fahrig, Rebecca; and Pelc, Norbert J., "Geometry Analysis of an Inverse-Geometry Volumetric CT System With Multiple Detector Arrays" (2004). Biomedical Engineering Faculty Research and Publications. 86.
https://epublications.marquette.edu/bioengin_fac/86
Comments
Published version. Published as part of the proceedings of the conference, Medical Imaging 2004: Physics of Medical Imaging, 2004: 320-329. DOI. © 2013 Society of Photo-Optical Instrumentation Engineers. One print or electronic copy may be made for personal use only. Systematic reproduction and distribution, duplication of any material in this paper for a fee or for commercial purposes, or modification of the content of the paper are prohibited.