When Leo Reina, president and CEO of Reina Imaging (Chicago, Illinois), a radiography repair and manufacturing company, first entered the business 32 years ago, long-bone imaging was still largely the purview of chiropractors and orthopedists. “Chiropractors would do it looking for curvature of the spine,” he recalls, “and as prosthetics became more common, more orthopedists started doing it for either the full spine or hip-to-ankle imaging.” As time went on, the technology was widely accepted as a means of diagnosing scoliosis, and it soon became part of radiologists’ armamentarium as well. “The current issue is the transition from film to digital operation,” Reina says. “We’re working to resolve imaging problems specific to those long studies, which require specialized equipment and training.”
While radiography in general has progressed naturally from analog imaging to CR to DR, Reina notes that long-bone imaging presents special challenges. “In long-bone imaging, the anatomy tends to be thick at one point and thin at another, so taking one single image to encompass all anatomy regions is a problem in terms of continuity,” Reina says, “and DR has not historically had any receptors large enough to encompass the entire anatomy.”
Long-bone imaging is a small market, but it comes with very specific needs. Traditionally, long-bone radiographs have been taken in steps, with the patient maintaining a single position while the technologist takes three exposures; these exposures are then stitched together to create a single image of the spine or leg. Today, technologies exist to stitch the images digitally, improving departmental workflow, but not eliminating the multiple-exposure problem.
“With these devices, I position the x-ray tube for the first exposure, have the patient hold perfectly still, and then take three shots,” Reina (who began his career as a technologist) explains. “I have three exposures to a patient, and as a technologist, I find that wrong. You should never do any more radiation exposure than is absolutely necessary.” This is especially true, he adds, when evaluating possible scoliosis, which is most commonly performed in the pediatric population.
With CR for long-bone imaging, it is possible to image the length of the spine or leg in a single exposure—but CR presents workflow issues, particularly in the handling of large (yet delicate) cassettes. As in other areas of radiography, the next logical step would be to move to DR—but, as Reina explains, until recently there was no DR panel large enough to take the image in a single exposure.
“The industry for doing full-spine imaging is very small,” he notes. “If the OEMs were to develop a single DR detector for long-bone imaging, they would never earn their money back. The next best thing is to take three DR exposures—but then the patient has to hold still for almost three minutes, and he or she receives more radiation dose than is necessary.”
For these reasons, iCRco (Torrance, California) developed its iDR Long Bone, a long-bone radiography platform that utilizes a 14” by 51” detector plate and eliminates the use of a cassette; the company is also developing a 17” by 51” version of the product. Reina explains, “It’s a system that uses phosphor plate technology in the detector, which allows for a higher resolution than DR anyway—and there are no cassettes involved. From a user’s standpoint, it’s the same workflow as DR: I position the patient and do a single exposure.”
The iDR Long Bone system works by sending image information from the detector plate directly to a scan processor; its wall-mounted, moving scan head enables the device to take the full image in a single shot, eliminating the need for image stitching. “This system works the same way the technologist did before, so it’s not difficult to incorporate into workflow, but it’s a single exposure,” Reina says. “From a user standpoint and an image-resolution standpoint, you might as well be using DR, but this is a lower-expense system that facilitates the ethical thing to do for the patient, in terms of radiation exposure.”
Because the system takes a single image, users can leverage compensation filters to balance out the exposure between thicker and thinner areas of anatomy, Reina says. “It’s clear plastic with a leaded glass in between, so that when taking a single exposure, I can use the filter to block radiation from the thinner part of the body,