CR or DR? You have x-ray technology options

CR or DR? You have x-ray technology options
By Terry Yochum, DC, DACBR

Technology is taking over radiology. And it is a good thing. Large films that do not always show a fine level of details, chemicals, and view boxes are being replaced by sharp digital images and computer monitors.

Digital imaging has many advantages. Once we acquire an image, we can:

If you have not yet converted to digital radiography, you will find two options available to you: computerized radiography (CR) and digital radiography (DR). Each has its benefits.

CR can be retrofitted to any existing x-ray equipment, regardless of which company manufactured the system. A CR system uses a cassette similar to a film-based process, but it has no film to load.

With the CR system, the cassette has a reusable phosphor plate that captures the x-ray photon’s energy and stores the latent image. The CR cassette plate is then placed into a scanner to convert the latent image into one that can be viewed on a computer monitor.

After the information is sent to the computer, the CR cassette plate is automatically erased and ready for the next exposure.

DR or (direct digital radiography) is now also available to any and all in our profession.

DR technology consists of a digital capture device that is mounted onto a wall stand or within a table utilized for imaging procedures. The most cost-effective DR technology uses a digital technology called CCD (charged couple device).

CCD systems use one or more high mega-pixel cameras to capture an image. The image is captured directly from a scintillator, with a field of view of up to 17 inches square, which replaces the traditional cassette and film combination.

The digital image from the CCD camera(s) is imported directly into a software program that allows manipulation and storage. This process takes approximately six seconds.

DR systems have been around for approximately six years; however, they were typically priced in the $300,000 – $450,000 range, which was too expensive for chiropractic radiology. Today’s systems have come down to a price point of about $75,000.

CR and DR each have advantages. Deciding between the two requires evaluating your practice with regard to patient volume and the types of exam you do.

In my practice, for example, I use an elevating table and a wall stand. DR is not the best solution for me, since it would require me to purchase two DR detectors and would also limit my ability to image lower extremities and patients who must be imaged in the recumbent position, using the elevating radiographic table.

DR systems available to chiropractors today are configured with the detector mounted only on a non-tilting wall stand. While it is possible to get one mounted in the table as well, the cost factor is prohibitive. Therefore, CR is the better solution for my type of practice.

On the other hand, one of the key advantages to DR technology is its speed. Once you make an exposure, you have an image preview in six seconds or less. Thus, many chiropractors with busy practices could see an increase in work flow and patient volume.

CR requires the use of cassettes, which is both good and bad. Cassette usage gives you greater flexibility for positioning and requires the least change to your imaging practices. After taking the exposure, you just scan the CR cassette plate.

This process takes about 40 – 50 seconds in the higher end systems, dramatic advantage over typical film processors.

Terry Yochum, DC, DACBR, director of the Rocky Mountain Chiropractic Radiological Center, in Arvada, Colo., is a respected chiropractic radiologist and international lecturer. In 1983, he authored the textbook Essentials of Skeletal Radiology, now in its third edition. He can be contacted at Dcrad099@aol.com.