S. Julian Gibbs

Patient risk from interproximal radiography

Computer simulation methods for determining patient dose from dental radiography have demonstrated that patient risk from a two-film interproximal examination ranges from 1.1 X 10(-8) to 3.4 X 10(-7) using 90-kVp beams, depending on film speed, projection technique, and age and sex of the patient. Further, changing from a short-cone round-beam to a long-cone technique with rectangular collimation reduces risk by a factor of 2.9, independent of other factors.

Qualitative and quantitative evaluation of charge capture by a radiology information system

Installation of a radiology information management system (RIS) is usually justified on the basis of improved departmental efficiency and improved charge capture. However, evaluation of the success of these expected improvements is often difficult. The installation and operation of such a system in a medium-sized tertiary care hospital has permitted the effects of the RIS on the operation of the department to be studied and the improvements in charge capture provided by the system to be quantitatively assessed. As a result of a side-by-side comparison with a conventional check-sheet manual billing system, it is apparent that the RIS reduces the errors inherent in manual systems. Subjectively, it is also apparent that personnel prefer the computerized system to the manual charge sheets.

DIGITAL RADIOGRAPHY IN THE ANALYSIS OF PAINTINGS: A NEW AND PROMISING TECHNIQUE

AbstractRecent advances in computer processing of images and the development of electronic x-ray detectors have made possible the development of digital radiographic techniques, which offer great potential for the analysis of paintings. The ability to distinguish very small differences in x-ray attenuation characteristics provides the possibility of quantitative analysis of pigment structures. The very sophisticated image processing techniques that have been developed for the space industry and medicine also may be applied to the analysis of paintings through the use of the digital radiographic images. In this communication, digital fluoroscopy, scanned projection radiography, and scanned point-source methods will be described. The virtues and limitations of each are noted. An initial experience with two of these methods will be the major subject of this communication.