Digital x-ray system rates FDA approval
For more than 60 years, x-ray film, in combination with intensifying screens, has been the standard medium for displaying medical images of the human body. In displaying these images, x-ray systems also perform the functions of image data capture, storage, and communication. Recently, however, advances in high-resolution monitors, optical storage systems, and high-speed communication networks have made the use of new electronic and imaging products technically feasible and economically viable to supplant x-ray systems for three of the four medical imaging functions--display, storage, and communications.
Despite these technology advances, however, there has been no method, until now, to effectively capture high-resolution x-ray imaging data in a digital format. However, at the recent RSNA meeting in Chicago, IL, Sterling Diagnostic Imaging (Greenville, SC) announced that the US Food and Drug Administration (FDA) had given clearance to market its Direct Ray direct-to-digital x-ray-capture technology.
This digital technology uses an amorphous selenium-coated thin-film-transistor (TFT) array to capture and convert x-ray energy into digital signals. It provides a full-field 14 ¥ 17-in. imaging area via a 2560 ¥ 3072 matrix of detector elements. By means of a bias voltage applied across the detector structure, incident x-rays generate electron-hole pairs in the selenium structure. These charges are collected by individual storage capacitors associated with each detector element for readout by customized electronics within the array. The result is a 16-Mbyte digital image that can be immediately reviewed on a monitor, forwarded over a communications network, stored, or printed.
Sterling plans to make the Direct Ray technology available through x-ray-equipment manufacturers and through its Sterling iiRAD family of x-ray capture systems. To date, Sterling has announced agreements with Fischer Medical Imaging (Denver, CO) and Acoma Medical Imaging (Wheeling, IL). It is also negotiating with several other manufacturers regarding the incorporation of Direct Ray technology into their equipment. Prototypes of the first two iiRAD products include the DR1000C, a dedicated chest x-ray system, and a general-purpose x-ray system. Both types of systems will be installed during the first half of this year.
