REDUCED DOSE AND IMPROVED IMAGE QUALITY WITH A COMPUTERIZED LINE-SCANRADIOGRAPHY SYSTEM

Diode-array digital radiography (DADR) promises to reduce patient x-ra y dose and improve diagnostic quality compared to conventional filmed radiography. DADR eliminates the detection of scattered x-rays by the geometry of line scanning. The x-ray tube is collimated to produce a f an beam of x-rays which impinges on a linear detector. The source and detector are held in alignment by a C-arm which scans the patient by t ranslating the assembly orthogonally to the detector aperture. Each im age line is exposed for a very brief time, which provides for a very s hort effective x-ray exposure and eliminates blurring due to patient m otion. The detector uses a patented combination of scintillator, fiber optic image guides, and self-scanning photodiode arrays which, in comb ination with scatter rejection, creates an electronic image having gre ater dynamic range than filmed x-rays. The image is converted to 12-bi t digital computer data which may be stored inexpensively, enhanced fo r improved diagnosis, and transferred to a PACS network. Images are di splayed in full 2352 x 2000 resolution on a high-bandwidth monitor. Di agnostic experiments have concentrated on chest imaging, an applicatio n for which Scantech is developing a new product. Patient dose is typi cally less than half that incurred with conventional techniques.