Two-year clinical experience with a computed radiography system

Abstract

Computed radiography (CR) is a radiographic imaging technology, announced in 1 981 [1], that generates a conventional radiographic image in digital form. The system has been gradually introduced into various clinical environments during the past 3 years [2, 3]. Currently, more than 80 systems are in operation, most of them in Japan. A CR system consists of two major components: (1) a reusable laser-stimulated luminescent phosphor imaging plate and (2) a scanning and recording mechanism. The imaging plate is housed inside a cassette similar to the one used in a film/screen system. Exposure to radiation causes a latent image to form on the plate. The plate is processed through a laser scanning mechanism for extracting the radiographic image, a process that is analogous to the development of a film. The extracted image can either be recorded on a lasersensitive film as an 8 x 10 in. (20.3 x 25.4 cm) or a 7 x 8.5 in. (1 7.5 x 21 .5 cm) hard copy or stored as a digital image. The latter can be archived to a digital storage device and displayed on a video monitor. Because the imaging plate has a much larger dynamic range than a film/screen receptor, CR has the potential of minimizing technical errors caused by overor underexposure as wall as lowering the radiation dose delivered to the patient. We installed the system (1) to investigate various clinical applications of this new technology, (2) to attempt to lower the radiation dose to the patient without sacrificing image quality, and (3) to use it as an image-acquisition device for our picture archiving and communication systems (PACS) [4, 5]. This report describes our experience with the system during its first 2 years in clinical practice. The Computed Radiography System and Its Accessories