Pairing CR & DR to Improve Care
Banner Health Del E. Webb Medical Center in Sun City West, Ariz., recently installed its first DR unit in its emergency room, primarily to help patient throughput.
The technological advancements of computed radiography and digital radiography have kept them relevant and key to timely, high-quality patient care. It’s not an either-or proposition, hospitals must find a way to use them both complementarily to harness the strengths of each to improve patient care.

Lost art of radiography

In 2007, Eliot Siegel, MD, director of radiology at the Baltimore Veterans Affairs Medical Center, bemoaned the possibility of general radiography becoming a lost art despite it being the most common imaging study performed in the U.S. Rather than look at plain films, residents want to see CT studies “when shown a chest radiograph at the American Board of Radiology examinations,” he wrote in Applied Radiology in June of that year.

Many promising technologies that Siegel singled out three years ago have become more commonplace, including portable cassette readers available in every hospital area that obtain images and portable digital radiography (DR), which Siegel called the “area with the greatest potential for improvement in digital radiography.”

Better throughput

When CR became routine many years ago, the rule of thumb was that one CR rad room could do the work of three film rooms in terms of patient throughput. Now that DR is being commonly used, it is expected that one DR rad room can do the work of six CR rooms. As hospitals utilize CR and DR, they can convert obsolete film and CR rad rooms into other more valuable space, such as ultrasound rooms or prep rooms, says Manuel Arreola, PhD, director of clinical radiological physics at Shands Hospital at the University of Florida in Gainesville, Fla.

Shands Hospital has been filmless since 2003. Throughout its two major hospitals, four community hospitals and three outpatient clinics, the hospital system has about 45 CR systems and eight DR systems. All CR systems are from Agfa Healthcare, while the DR systems are from Siemens Healthcare, Canon USA and Quantum/Agfa.

When choosing either a CR or DR system, Arreola seeks out units that are, among other attributes, very user friendly. “You want your technologists’ focus to be on the patient and not on the amount of buttons they have to push or the number of screens they have to go through before they can take the picture,” he says.

Kerrie Short, senior clinical manager of medical imaging at Banner Health Del E. Webb Medical Center in Sun City West, Ariz., agrees. “New technology can sometimes be complicated when it doesn’t have to be. It’s very important for the CR and DR systems to be easy to use,” says Short, who uses equipment from Fujifilm Medical Systems.  

In the ER

Banner Health has a combination of CR and DR in the emergency room (ER), with only CR in the main department. Short and her colleagues transitioned to CR about five years ago, while their move to DR took place within the last year and will gradually increase. The impetus to deploy DR in the ER is faster throughput of critically  ill and trauma patients.

“With no cassettes to handle and an immediate image to evaluate, technologists and radiologists can significantly reduce the patient’s time spent in the ER,” Short says. “It’s about patient care. If we can make a diagnosis faster and with more confidence, then that patient will be better served.”

But DR is not the right choice in all clinical situations. “In the ER, DR must always be used in conjunction with CR,” says Arreola. “DR alone cannot give 100 percent flexibility in terms of the views that need to be taken.” Trauma patients in discomfort may have limited mobility in terms of positioning extremities. “The flexibility of having CR cassettes to place between the patient’s extremity and the trauma board is crucial,” he says.

While portable DR will have an increasingly important role, Arreola says it will not be in his ER. The main reason is the differential in cost between the CR cassette and the portable DR detector—around $1,000 versus $120,000. “The strength of the ER is having a dozen people tending to a patient. With all that goes on in the ER, you don’t want to be worried about dropping or damaging a costly portable detector,” he says.

In the ER at Massachusetts Hospital (MGH), both CR (Agfa) and DR (GE Healthcare) are utilized, according to Thomas Ptak, MD, a trauma and emergency radiologist and assistant professor of radiology at Harvard Medical School. Ptak agrees that both modalities complement each other.

DR allows for flexibility in terms of quality because you manipulate the images or repeat them immediately if necessary. DR processes the images immediately, optimizing the radiologist’s ability to make a diagnosis, Ptak says. CR, on the other hand, offers the advantage of being portable, “to capture images remotely in difficult circumstances,” he says.

An advantage of modern radiography in general is its ability to optimize the radiologist’s relationship with the trauma patient, Ptak says. “It’s the closest thing to actually being with the patient and making a decision on the spur of the moment as we’ve ever had. If we need an additional image, the patient is still there. I can talk to the patient; I can see the patient. If I see something on the image, I can ask the patient a question. It’s as close to interactive as we’ve ever been.”

Radiation concerns

The Alliance for Radiation Safety in Pediatric Imaging expanded the Image Gently radiation dose initiative from CT and interventional radiology to CR/DR exams. Steven Don, MD, head of the Image Gently CR/DR initiative and associate professor of radiology at St. Louis Children’s Hospital in St. Louis, says that radiologists and healthcare personnel have to do everything possible to lower radiation dose.

“Standard x-rays utilize far less radiation than advanced imaging procedures such as CT, but because they are so commonly performed, they present a significant opportunity to lower the radiation dose that children receive each year from medical imaging,” says Don.

Arreola and his team completed a project last year where they modified settings on the CR and DR units in the neonatal intensive care unit. The setting is lower than usual in terms of radiation exposure, but does not hinder image quality. “These babies often spend weeks recovering and can be imaged on a regular basis. We have taken steps to ensure their radiation dose exposure is as low as possible,” he says.

At a Digital Radiography Summit in February to introduce the CR/DR Image Gently initiative, the American Association of Physicists in Medicine and the International Electrotechnical Commission agreed to work together to create a unified standard for CR/DR radiation exposure indexes. In addition, the American College of Radiology said it will develop a CR/DR registry to help develop national benchmarks for quality and dose optimization.

Improved technology

While the distinction between CR and DR, in terms of technological advancements, has become blurred, it is still important for radiologists, technologists and IT personnel to understand the strengths that each modality can bring to the enterprise, whether in the main hospital or the ER. CR is considerably less expensive than DR and has therefore been the initial way for many facilities to go filmless. Additionally, the speed offered by DR has become the default way for many emergency rooms to enter into the digital radiography revolution. The key now is for these institutions to find the optimal balance between the two complementary x-ray systems and to use them in conjunction to provide better patient care at the most reasonable cost.