In the years since its introduction, digital radiography (DR) has proven itself an efficiency-enabling technology in small community hospitals and large regional health systems alike. It is doing the same in teaching hospitals, helping those institutions fulfill their academic missions. Sheryl Abercrombie, service director of radiology, University of Kentucky Medical Center, Lexington, says, “The speed and flexibility of ddR enable attending radiologists to be faster at completing their work and, thus, to have more time available to devote to the education of residents. The ddR images are obtainable in a very consistent form over time, which is crucial to helping us in our goal of teaching students and residents how to notice subtle changes in anatomical structures.”

The University of Kentucky Medical Center is a level-I trauma center with nearly 450 beds. A range of imaging services are offered there, including CT, MRI, nuclear medicine, ultrasound, mammography and, of course, general radiography. The center’s 23 radiologists and 60 technologists worked extensively with plain film until the enterprise went digital in 1996. Computed radiography (CR) was brought in as an initial replacement for film, but was eclipsed by DR not long after the first of three direct digital Radiography ddR machines from Swissray International was installed in 2003.

All three of those ddR units are deployed in the Kentucky Clinic (the university’s on-campus outpatient center). Swissray systems are fundamentally different from other machines in that they do not rely on a flat panel detector; instead, they use a more durable detector system containing a scintillator that converts the radiation dose to light, which then is captured in digital form by an array of four charge-coupleddevice (CCD) cameras.

“We had been watching ddR technology evolve for several years prior to our purchase,” Abercrombie says. “We noted that selenium-plate technology was vulnerable to damage. Being a level-I trauma center and an academic facility, we have lots of students coming through, so we are not always as kind to our equipment as we should be. As such, we were leery about the potential costs involved in having to replace damaged selenium plates, which are expensive. That was a key reason why we decided to invest in ddR .”

BETTER SERVICE

For Penny M. Olivi, MBA, RT(R), senior administrator, department of diagnostic radiology, University of Maryland Medical Center, Baltimore, the value of DR in supporting the academic mission derives simply from the fact that it is state-of-the-art technology. “It enables us to introduce those being trained as technologists and physicians to new, important technologies, and ddR certainly qualifies as that,” Olivi says. Three Swissray units have been installed, one in the main radiology department, and two in the emergency department.

Olivi’s statements are echoed by colleague Lois N. Harris, RT(R), chief technologist. She says, “We deployed as we have with ddR because we wanted to be on the cutting edge, but we also wanted a technology that would help us provide better day-to-day service to patients.”

At 648 beds, the University of Maryland Medical Center is one of six hospitals in the University of Maryland Medical System. Among the nation’s first teaching hospitals, it started as the Baltimore Infirmary, built in 1823 by physicians from the University of Maryland School of Medicine. The facility now provides comprehensive health care services and is a regional referral center for the treatment of adult and pediatric cancer, trauma, heart disease, and neurological conditions. In 2003, it logged 29,697 inpatient admissions (including newborns) and more than 16,250 surgeries in 19 high-tech operating rooms; outpatient visits totaled 156,290. All of the more than 1,000 attending physicians are University of Maryland School of Medicine faculty members.

Because of the volume and variety of patients seen, Harris believes that her enterprise will not be able to replace film and CR completely with ddR. “We have too great a reliance on machines that are portable,” she says. Nonetheless, Harris finds ddR highly valuable. “In the long run, it helps bring down our costs,” she says. “CR cassettes and screens are very expensive. Our reduced use of those saves money, which can better be spent on fulfilling our academic mission.”

IMAGE QUALITY

One of the chief advantages of ddR is that it allows more productivity than is otherwise possible with either plain film or CR. Abercrombie reports that, prior to ddR , her department struggled to achieve a throughput speed of 1 patient every 30 minutes for imaging the entire spine. “Usually, it was more like a patient every 45 minutes,” she says. Thanks to ddR , a patient requiring a full spinal study is in and out, and the room is readied for the next use, in only 15 minutes, Abercrombie reports.

The explanation for the remarkable gain in speed is found in the workings of the ddR detector. Unlike the flat panel type, this detector charges and relaxes almost immediately, which permits technologists to take exposures at the rate of once every 2 seconds, according to Swissray. Those exposures are then viewable less than 5 seconds later, and can be electronically manipulated on the spot to enhance desired characteristics or features of both bone and soft tissue. Thus, productivity gains of 20% to 30% and more are common for ddR users. “Another reason that you can be more productive with ddR , in general, is that, unlike CR imaging, ddR does not make you gather up needed equipment, carry it to the room, carry it out, and then wait in line for a chance to identify and process the images,” Harris says.

Moreover, various features of the machine (such as a motorized and programmable C-arm that automatically swings the imagemaking components into precise position and a specially designed multipurpose table that is rigid enough to ensure no distortion of images, regardless of the severity of the shot angle) contribute to faster throughput by making it easier to acquire images.

“In our outpatient department,” Harris says, “a lot of things that we used to do with the patient on the tabletop, we now do with the patient erect, just because of the ease of operation. With the patient erect, we can move from chest view to spine view much more rapidly than if we had to work with the patient in a supine position. That is important because, with patients who are difficult to move onto the table and position correctly, it is better to be able to image them erect.”

Image quality is, of course, at least as vital as throughput speed. “Image quality is what drew us to ddR in the first place,” Abercrombie says. “Our physicians were trained to work with film, so they had some difficulty adjusting to CR. Unfortunately, their eyes saw the quality as something less than what they were accustomed to getting with film. In our outpatient clinic, 50% of the business is orthopedic, and those orthopedists do a lot of templating work: hip replacements and knee-joint replacements. Other orthopedic physicians do a lot of scoliosis spinal work.” All of them need to be able to work with electronic images that have quality matching, or even surpassing, that of film. Abercrombie continues, “We were able to provide that kind of quality with ddR . Image quality was superior to what we were seeing in plain film. It even allowed us to provide orthopedists with specialty views such as sunrise views of the patella.”

The ddR machines acquired by the University of Kentucky were engineered with a fixed focal length of 1.5 m. Abercrombie notes that this took a bit of getting used to by technologists, who, until then, had been workingwith equipment operated at a distance of 1 m or 1.8 m. “We have done a lot of comparison studies looking at chest images acquired at 1.8 m versus 1.5 m to determine if we were, in some way, doing the patients a disservice by imaging at 1.5 m. We found no negative implications due to the fixed distance,” Abercrombie says.

Harris indicates that, in technologist retraining for ddR , “There were difficulties only in that we had to teach people to think outside the box when using ddR ,” she says. “Otherwise, educating the technologists was a relatively straightforward process.”

USER SATISFACTION

At the University of Kentucky, if ddR is causing any grumbling at all, it is from technologists in parts of the enterprise where the machines have yet to be installed. The eager ones are “hearing from their colleagues in the outpatient center how great ddR is, so they are demanding to know when they are going to be able to get their own hands on it,” Abercrombie says. She mentions that, for those technologists awaiting ddR ‘s arrival, one of the eagerly anticipated benefits is freedom from having to handle CR cassettes all day. “The line we keep hearing from them is, If I never have to lift another cassette to take an image, I am going to be thrilled.’ They notice that the technologists using ddR are no longer suffering from the minor strains common to technologists.”

Among the technologists who are using it, ddR has been a huge morale booster. “They are amazed at the ease and quickness to obtain an image in just a few seconds,” Abercrombie says. “They are moving more patients through than ever but, at the end of the day, they are no longer physically or emotionally exhausted.”

Abercrombie indicates that she would like to add more ddR units before long. “Our hope is to expand our outpatient imaging center, which means that we would need to install three or four ddR units there alone,” she says. “Our goal, as well, is to take this technology into our emergency department. Because we are a level-I trauma center, there is a huge need to image patients quickly, yet still be able to produce a quality image.”

The idea of ddR in the emergency department is particularly enticing to the University of Kentucky. The fact that the ddR detector is an enclosed unit, Abercrombie notes, minimizes the risk of contamination from body fluids. It is also possible to place the trauma patient on a radiolucent table immediately upon arrival in the emergency department and keep that table with the patient as he moves between the ED and radiology areas. “This would spare the patient the need to be moved from a triage table to a separate imaging table and then back to the triage table,” she says. “Since the patient would not have to be moved from table to table, this would reduce the risk of causing the patient further injury or discomfort.”

As part of the University of Kentucky’s disaster planning, one room in the outpatient center still is film-based. “In the event of a catastrophic occurrence, such as a network shutdown, we will want to have at least one recourse to fall back on, and that is film.” That will not be true forever, though. The university is in the process of hardening its infrastructure and building in multiple fail-safe redundancies that ultimately will negate any need for an analog fallback plan. “In time, film will go away entirely,” Abercrombie says. “In this era of faster and more with less, ddR is the perfect answer.”

Rich Smith is a contributing writer for Decisions in Axis Imaging News. The views expressed in this article by Sheryl Abercrombie are those of Abercrombie and do not constitute an endorsement of this product by the University of Kentucky.