11 April 1996 Low-exposure scanning-beam x-ray fluoroscopy system
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A prototype scanning-beam digital x-ray system for cardiac fluoroscopy has been constructed. Source-to-detector distance is 94 cm with the subject positioned near the source. The 4-kW source operates at 70-110 kVp and has an electromagnetically-scanned 25-cm-diameter transmission target. The target is at ground potential and is directly liquid cooled for continuous full-power operation. The source collimator has 22,000 holes whose axes are aligned with the center of the detector array. Beam divergence through the 0.38-mm-diameter collimator holes is matched to the 1.8-cm diameter of the detector array. The detector is a 96- element scintillator array optically coupled to a 96-channel photomultiplier tube. A narrow (0.6 degree half-angle) x-ray beam scans the 19-cm-diameter field of view at 30 frames/sec. A two-dimensional shift-and-add reconstruction algorithm produces a narrow-angle classical tomographic view of the subject in real time. The small detector area and large patient- detector distance result in negligible detected x-ray scatter. Signal-to-noise ratio is calculated to be equal to conventional fluoroscopic systems with ten times less patient skin exposure and better than four times less patient integral dose. Exposure reduction is due to the elimination of x-ray scatter and the anti-scatter grid, increased detector DQE, and geometric considerations.
© (1996) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Edward G. Solomon, Edward G. Solomon, Michael S. Van Lysel, Michael S. Van Lysel, Robert Erhard Melen, Robert Erhard Melen, Jack W. Moorman, Jack W. Moorman, Brian Skillicorn, Brian Skillicorn, } "Low-exposure scanning-beam x-ray fluoroscopy system", Proc. SPIE 2708, Medical Imaging 1996: Physics of Medical Imaging, (11 April 1996); doi: 10.1117/12.237777; https://doi.org/10.1117/12.237777

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