Sometimes called Cassetteless Radiography, actually a misnomer, CR still uses special cassettes to render a computerized image. Instead of using conventional film/screen detection, a special image plate is inserted permanently into the special cassette. Ionizing radiation produces ionizing patterns in the imaging plate (IP) corresponding to tissue and bone density. Instead of unloading film into a processor, the technologist feeds the cassette into a digitizing decoder or "Reader". The ionizing patterns on the plate are then converted into digital information and assembled by a PC and special processing software to produce an x-ray image in a matter of seconds. CR still requires manual transport of each cassette as in days past, but the need for film and chemistry and two minute processing time is thus eliminated. CR offers considerable cost advantage over Direct Radiography, and most film companies are supporting this mode, as it offers a familiar environment to the technologist, and they can still market cassettes.
With Direct Radiography (DR), the patient is placed on the table as usual, but from there on, the examination procedure is much different. A permanent receptor has replaced the conventional bucky, and as soon as the x-ray is terminated, the receptor immediately feeds the acquired digital information to the processing system (PC) without the need for cassette transport. Consequently, films can be taken as fast as the patient be positioned, dramatically reducing the length of the exam, resulting in increases in productivity by an order of magnitude. However, the extremely high cost of the image receptors, made only by a few manufacturers, has kept the acceptance level down to only the high-volume hospitals and imaging centers.
As with any new emergent technology, the "new" finally wears off, and the rules of supply and demand take over. Initially, the high cost of CR equipment could not be realistically offset by any kind of savings offered by the elimination of film and chemistry. However, as production techniques improved and demand forced the increase of sales, prices started moderating to the point that supply cost savings could be effectively applied to payout and up-keep of a CR unit. Imagine the payments on a fully loaded 4-wheel drive Suburban weighed against your normal monthly x-ray supply and processor maintenance expenses. There probably would not be a lot of difference.
Taking Your Work Home - Not a popular phrase back in the '70's, but necessary in the fast moving environment of our new millenium. Now, patient information and images at the practioners' office is instantly available at home, 24 by 7. Thanks to Picture Archiving and Communications Systems (PACS), and high speed internet, all patient image information is organized and stored in logical sequence allowing viewing from a remote location.
HIPAA - Protection of patient information has become a hot-button for legislators, and the entire health industry. Digital imaging processing systems based on the DICOM standard provide for various levels of redundancy to protect against the loss of patient data. Examples include:
- Backup to CD or DVD for off site storage. (Small facilities, least expensive method)
- Removable transportable hard drives. (Medium sized clinics)
- Large arrays of hard drives with automatic backup features. (Imaging centers & small hospitals)
- Off-Site rental data storage facilities, with restore capabilities. (All facilities)
- Time Is Money
- 1) Bottom line, digital imaging means less time spent with the examination. In a busy work environment, this translates to less waiting time and less processing time for the anxious patient. It also means more patients can be processed in the same given amount of time. The technologist may then devote remaining time to other duties.
- 2) No longer will loan films have to wait for the U.S. Postal service or hand delivery. Images may be zipped off to referring physicians via e-mail and received instantaneously for comment.
