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Crepeau, R. L.

Publications and source records attributed to Crepeau, R. L..

5 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS1975

The capability of fluoroscopic systems to determine differential Roentgen-ray absorption

A clinical fluoroscopic unit used in conjunction with a TV image digitization system was investigated to determine its capability to evaluate differential absorption between two areas in the same field. Fractional contrasts and minimum detectability for air, several concentrations of Renografin-60, and aluminum were studied using phantoms of various thicknesses. Results showed that the videometric response, when treated as contrast, shows a linear response with absorber thickness up to considerable thicknesses.

Baily, N. A.↗
NASA NTRS1974

Fluoroscopic tomography

A fluoroscopic tomography system capable of synthesizing body sections at a number of levels within the body has been developed. The synthesized body sections may lie either in a range of planes parallel to, tilted with respect to, skewed with respect to, or both tilted and skewed with respect to the plane of motion of the X-ray tube target. In addition, body sections can be presented which are contoured to the patient's anatomy. That is to say, they may even encompass such complex surfaces as a quadratic hyperplane. In addition, tomograms of organs in motion can be imaged.

Baily, N. A.↗
NASA NTRS1973

Electrofluoroplanigraphy.

The authors describe a fluoroplanigraphic method of synthesizing single-plane sections of any desired layer within the body. This is done by appropriate positioning of the individual images obtained at various locations of the X-ray tube during a single tomographic motion, followed by electronic summation of each roentgenogram. A TV image of any desired body section is available within seconds of the original recording sequence.

Baily, N. A.↗
NASA NTRS1971

Capabilities of a single scan TV-radiographic system for digital data acquisition.

A single scan TV-radiography system capable of providing analogue signals ready for A-D conversion for input to a computer has been investigated. Modulation transfer functions of both horizontal and vertical resolution have been obtained. The capability for gray scale reproduction was also investigated. The output data rate of the system is 16 KHz thereby providing compatibility to A-D converters generally available for most computers. In general, the capability of the system was found to exceed the input capabilities of available image-amplifiers and is therefore acceptable for quantitative fluoroscopic applications.

Baily, N. A.↗