Medical Imaging talks to vendors, technologists, and managers about how the two modalities compare on the medical stage.

If CR (computed radiography) and DR (direct radiography) were on a reality show today—let’s say an American Idol of the medical world—the two would very likely be facing each other in the finals. DR would be the contestant with fresh appeal and a faster tempo. CR would be the contender whose range and abilities show more flexibility but whose style is not necessarily next-generation.

Unlike the American Idol winner who will be chosen by summer and selected more because of popularity than ability, the CR versus DR competition is likely to play out for some time to come and will, in the end, be judged by performance.

The competition between the two modalities is as tough as that among the singers on television. From the technologist’s perspective, CR and DR are fairly well matched. Both are digital modalities and offer related advantages. “The advantage of having a digital image, whether CR or DR, is that you have a wider dynamic range and can take advantage of advanced processing tools that can enhance the image,” said Penny Maier, director of marketing for imaging systems at FUJIFILM Medical Systems USA Inc, Stamford, Conn. The postprocessing functions are often the same, whether CR or DR.

Fredrick Walker, a radiology technologist at Sharp Rees-Stealy in San Diego, offers an example. “If an image is too dark, we can now window it or shadow it or make it lighter without having to reshoot,” he said. This exposes the patient to less radiation and permits faster exams than was achieved with traditional x-ray film technology.

Agfa’s CR 35-X is a highly versatile digitizer with a small footprint that is specially designed for decentralized CR environments. The CR-85-X is a multiuser digitizer, featuring a 10-cassette drop-and-go buffer that eliminates waiting times and maximizes productivity.

Depending on the vendor, the workstation and interface may be the same for both CR and DR. “Techs have the convenience of using the same tools, and radiologists see images with the same look and feel regardless of where the image was acquired,” Maier said.

But the process of getting to that point is quite different. The most obvious contrast between CR and DR is image acquisition. Cassettes, standard to CR, are eliminated in the DR workflow, resulting in two major advantages for the technologist: fewer repetitive motion injuries and faster acquisition times.

Alan Hill, lead technologist at Kaiser Fair Oaks in Fairfax, Va, experienced degenerative changes in the bases of his thumbs using CR, which prompted a switch to a DR system by Canon USA Inc, Lake Success, NY. “Every time I took one image with CR, I handled the cassette six times. Since switching to DR, the problem has disappeared,” Hill said.

Workflow has also been streamlined. “The fastest time we clocked using CR was 35 seconds per image. For DR, the same process was 3 seconds,” Hill said.

Tim Martin, radiology director at Cabell Huntington Hospital in Huntington, WV, has made similar comparisons. “DR acquires images in about 6 seconds versus 45 seconds for CR. DR really streamlines workflow, so the time frame from patient setup to image acquisition is less,” Martin said.

Faster acquisition results in shorter patient visits and therefore greater patient satisfaction. “Once the patient is in radiology, an exam that used to take about 25 to 30 minutes now takes about 10 to 12 minutes using DR,” Walker said. Not only is a quick visit more convenient, but it may also be less stressful, particularly when results are reported more rapidly.

“The turnaround time for physicians receiving images using DR versus CR is a lot faster, so by the time a patient leaves our department and goes to see the physician upstairs or down the hall, the images are readily accessible to the providers,” Hill said.

Sally Grady, director of imaging services for Florida Hospital Celebration Health, Celebration, Fla, doesn’t believe that the timing makes that much of a difference for providers, however. “A radiologist doesn’t really care if it takes 2 minutes or 5 minutes to produce an image. All they care about is quality,” Grady said.

In this area, however, there is no clear winner. Some, like Grady, believe that CR provides better-quality images. “With our new software [MUSICA2—Multi-Scale Image Contrast Amplification—from Agfa Healthcare, Mortsel, Belgium], the images are so detailed, I can see toenails on a foot x-ray or braided hair down someone’s back on a chest x-ray,” Grady said.

Martin, also an Agfa customer, has experienced exactly the opposite. “In my experience, DR gives you better image details, and although doctors for the most part do not regularly bring it up, they have commented that DR image quality is a little better than CR,” Martin said.

Where CR still holds a clear advantage is in its flexibility and portability. “The big advantage CR can provide to a technologist in a clinical application is the flexibility the cassette brings in a trauma environment or the OR, where you need to position a cassette to record an anatomical area in an unusual place or as a lateral,” Maier said.

Grady concurs. “You can do any exam type using CR: portable, cross-table, cubitus,” Grady said. Patients who can’t be moved or can’t move easily, such as those in wheelchairs or wearing casts, benefit from the increased flexibility of the cassette, possibly experiencing greater comfort during the exam.

Here too, however, the differences are narrowing as DR manufacturers debut new systems. Canon offers portable DR systems that extend DR applications to neonatal and trauma. Fujifilm also offers a portable system, the FCR Go, as well as the new Unity SpeedSuite system that features a u-arm that can rotate around the patient to accommodate lateral views.

Fujifilm’s Unity SpeedSuite features a single-detector design to lower costs while maintaining image quality.

The Votes

Despite these advances, CR is not in immediate danger of being voted out of the hospital. “A lot of our clients love the idea of being all DR, but overwhelmingly we see that coexistence is absolutely necessary because of the need for portability and flexibility, particularly in the OR and trauma areas,” Maier said.

April Hammarsten, central region radiology supervisor at Sharp Rees-Stealy, whose institution uses Fujifilm systems, is one such customer. “Ideally, we’ll have one of each type at any site,” Hammarsten said. If forced to choose, however, she would select a DR unit and maintain a carbon reader and cassette option for extended work if needed.

Grady would vote the other way, choosing to keep CR or hybrid systems in place. Celebration tried DR in two of its sites but removed the units when quality did not match that of the CR systems. The impact on efficiency has been minimal. Celebration is located about 2 miles from the Walt Disney World Resort in Orlando and handles about 55,000 emergency department visits annually. “Turnaround is extremely important. We are using a new product that is almost a CR/DR hybrid—a single-plate reader with a very fast image print time—and I can usually see images in 10 seconds or less,” Grady said.

She acknowledges that DR can increase productivity but also suggests that the difference can be reduced with smart planning. By placing the hybrid-type units directly in control rooms next to the exposure panels, Celebration has been able to maximize productivity. “By the time the technologist has positioned the patient and dropped the plate, they are able to see the image before they go out to reposition the patient—the tech can only go so fast,” Grady said.

Analysis of 388,000 radiographic exams completed in a 6-week time period showed that the average time for a CR scan at Celebration from start to finish was 8 minutes, a turnaround comparable to that for DR as measured by Hill, Martin, and Walker. Throw in the high cost of DR and Grady predicts that CR, particularly hybrid units such as the one she uses, will be around for a very long time.

Hill is not quite as optimistic regarding the future of CR. “DR is definitely the way of the future. I think we are going to see CR become an obsolete modality within the next 3 or 4 years,” Hill said. Though many don’t agree it will occur that quickly, DR does have its proponents who believe that the biggest obstacle to its domination is its expense.

“DR is still fairly pricey. Most technologists and managers will say they would like to go completely DR, but due to the expense, most institutions are evolving in steps,” said Martin, who notes that is the approach Cabell Huntington Hospital has taken.

Martin thinks it’s more a question of return on investment. “I think most facilities and institutions that currently have CR definitely want to make sure they realize the return on investment they’ve put into it. In 5 to 10 years, CR will still be around, though most places are in the process of phasing CR out,” Martin said.

Canon DR can be integrated into existing fluoroscopic and radiographic rooms without the facility having to replace its existing equipment.

Those who have compared the long-term cost of the two systems believe they are comparable and that perhaps DR offers a better deal in the long run. The ability to handle a greater volume of patients means more revenue generation and greater efficiency. DR devices often require less space than CR units, and the extra room can be used to install more units or fulfill other needs, such as physician and staff offices. “DR gives you more throughput with less real estate in your department, which is a big issue. We are always looking for extra space to grow into,” Martin said.

Some departments may also be able to reduce personnel costs, either through the elimination of technologist positions, leaving them unfilled or replacing them with a lesser-paid employee, such as an imaging assistant. This position would then get patients in and out and handle any paperwork while the technologist remains in a designated exam room and focuses on shooting images. “If you can utilize an imaging assistant to take the place of a technologist, you can cut the salary budget in half,” Hammarsten said.

The elimination of cassettes not only deletes the consumables costs (Hill estimates this expense at $2,000 to $5,000 per cassette; Hammarsten pays about $1,800 for 14 to 17 units) but also results in less related expense for workers’ compensation and less time off for technologists suffering from repetitive motion injuries. “DR costs more up front, but I think the maintenance of CR ends up costing more,” Hammarsten said.

The Results

With DR and CR expected to share the stage for some time to come, technologists can make themselves more marketable by learning both methods, although nearly everyone concurs that they are not in danger of being sent home early without this experience. “Hospitals want to know your experience, but either way, they will train you. I’ve hired techs who have never worked with CR,” Grady said.

Generally, the basic radiographic principles are the same and are learned in school. Older technologists accustomed to film are therefore not at too great a disadvantage unless they are extremely intimidated by computers. Most importantly, technologists need to be open to learning a new system. There is a learning curve as systems move from conventional film to digital and from CR to DR, but it need not be intensive or complicated. “The training is so simple that you can take techs coming directly from film and train them in a DR environment and they will be successful. Even older techs who are computer illiterate will eventually catch up,” Hammarsten said.

Many of today’s systems strive to maintain as user-friendly an interface as possible. Hill notes that the techs at Kaiser Fair Oaks were trained on a new DR system with just one 48-hour in-service. “If you do go to a new facility that has equipment you are not familiar with, there is usually a training process. In general, you’ll train on the technology that will be applicable to what you are doing,” Hill said.

“Being comfortable with the computer and understanding x-ray principles will position a tech very well for CR as well as DR,” Maier said. Naturally, the more you can do, the easier it may be to gain employment, but no one has suggested that technologists need to know everything nor do they need to specialize.

“To a certain extent, you always want to try to find the highest quality of professional that you can, but the way the market is right now for technologists, we feel very fortunate to be able to hire them with CR experience. DR experience is a plus,” Martin said.

So just like on American Idol, for digital radiographic technology and technologists, the instrument doesn’t matter so much as the ability to perform and win over the audience.

Renee Diiulio is a contributing writer for Medical Imaging. For more information, contact .