CR and DR come to the rescue in emergency departments

November 9, 2005

State-of-the-art digital imaging services are being prescribed to treat a crisis of overcrowding in the nation’s emergency departments. The need for speed is a driving factor.

State-of-the-art digital imaging services are being prescribed to treat a crisis of overcrowding in the nation's emergency departments. The need for speed is a driving factor.

At a time when the number of hospital emergency departments has been cut by 12%, ED visits reached a record high of nearly 114 million, 23% higher than a decade earlier, according to 2003 data released in May by the Centers for Disease Control and Prevention.

The crisis translates into a clear need for higher patient throughput and expedited diagnosis and treatment. Computed radiography and digital radiography are two imaging tonics to help relieve overcrowded trauma bays. DR's greater speed and lower radiation doses make it the more attractive choice, but CR also has advantages, and combination systems have begun to emerge.

"The biggest trend is that most emergency departments are replacing film systems with either CR or DR systems," said Todd Minnigh, Kodak Health Group's director of marketing for the Americas.

Both CR and DR have a legitimate role in any emergency department.

"In many cases, both can rightly coexist, as each has certain advantages," said Ray Russell, executive director of marketing at Agfa Healthcare.

The primary advantage of DR is the ability to have a high-volume/throughput x-ray room centrally located. The advantages of CR are portability, 100% exam coverage (e.g., cross-table laterals), and leveraging of existing sunk costs in portable and/or stationary x-ray equipment, Russell said.

DR has other benefits as well. Amorphous selenium detectors offer a more efficient method of collecting image information and therefore can often deliver improved images and lower radiation doses than CR systems. DR systems also provide at least twice the speed and productivity of CR systems, which still require a technologist to walk cassettes to a processor.

DR systems are, however, more expensive and require installation of a new x-ray system.

"The general consensus is that DR systems are especially appropriate for ED settings and areas with extremely high patient volumes, while CR systems are best suited for general radiology, intensive care units, portable exams, and outpatient imaging centers," Minnigh said.

CR serves most general radiology exam rooms and brings digital imaging to remote locations, particularly for those facilities either wired to PACS already or positioning themselves for PACS, according to Arne Helbig, international marketing manager for Philips Medical Systems. It remains the most affordable way to convert to digital workflow.

"CR will remain an affordable means to digitize existing radiography equipment," Helbig said.

The ED faces the need for minimal patient movement, complex projections, and decreased accessibility to the patient due to intubation, monitoring equipment, and cables. CR is sometimes used here to supplement DR, which has limitations in certain views. CR's advantage comes from its compactness and simple positioning.

While the quicker image appearance of DR is attractive in the emergency room, the superior positioning flexibility of CR cassettes makes CR the easier technology to employ there, according to Clay Larsen, vice president of marketing and development at Fujifilm Medical Systems USA. Compact, in-room readers eliminate cassette transport, so the time-to-image appearance difference is negligible.

The ideal scenario is an integrated CR-DR solution, which some manufacturers are now beginning to ship. Integrated CR-DR systems allow flexibility in selection of target receptors - DR detector or CR cassette - during the exam. Results are presented on the same back end, in the same patient folder, with virtually identical image quality.

EDs are among the first hospital areas to embrace digital imaging because of its enhanced speed and the ability to simultaneously route images to multiple locations, enabling emergency physicians to view images while consulting with remote radiologists.

"The greatest impact digital radiography has afforded us is the ability to rapidly review a study and simultaneously discuss the case with the radiologist," said Dr. L. Albert Villarin, director of medical informatics in emergency medicine at Albert Einstein Medical Center.

Prior to DR and PACS, wait times from order to film-in-hand could be as long as two to three hours, Villarin said.

One spinoff of a state-of-the-art digital imaging emergency department is techno prestige.

"The clinical driver is obviously most important, but we're also seeing increased provider satisfaction, including the ability to recruit and retain clinical staff looking to work at a cutting-edge institution," said Dr. Chris DeFlitch, director and vice chair of emergency medicine and physician champion of clinical information systems at Penn State Hershey Medical Center, site of an all-digital ED.

At the same time, DeFlitch cautioned other institutions considering similar configurations to be careful what they wish for.

"You have to know what you are getting into," he said. "You have to understand how the work gets done in your institution before you can even contemplate digital radiography or clinical information systems. They are only tools, and tools can be used or misused."

The principal lure of DR remains its speed. Near-instant imaging and faster triage, intervention, and treatment can translate into better outcomes. Procedures that once took 15 to 45 minutes can be performed in less than 10 minutes. Preliminary images are available within seconds and full-resolution DR images in as little as 35 to 45 seconds.

DR systems have also become more flexible, with detectors mounted on movable columns that can be positioned in all three dimensions. One new driver steering DR into emergency departments is its portable capability.

"We are definitely seeing more emergency departments considering DR as a solution for their x-ray needs of critically ill patients, thanks to the introduction of portable DR," said John Allen, a senior marketing and sales manager for Canon Medical Systems.

Canon introduced portable DR in 2001 and remains the only manufacturer shipping this technology. Weight-bearing, cross-table C-spine, decubitis KUB and chest, sunrise knee, and bedside are just some of the studies that had been possible only with conventional x-ray or CR but are now possible with portable DR.

Darrell Johnson, GE Healthcare's marketing manager for the Americas, expects portable DR technology to have an enormous impact on market penetration.

"We see the role of DR changing exponentially with digital portables, specifically in ED and trauma rooms," Johnson said.

The general DR market stance appears to be on firm footing. A 2004 Frost & Sullivan report said total world DR market revenues were $376.5 million in 2003 and were expected to reach $828.7 million by 2010. The report predicted an annual growth over the next five years of 11.9%, with the fastest growth occurring in Japan. The largest markets remain in North America and Western Europe.

At the time of the report, there were 18 market participants, including most major multimodality medical equipment manufacturers, several medium-sized competitors with DR-focused product lines, and smaller niche players. Today, every second digital package installed in the U.S. is a DR system, according to Regina Radtke, director of product marketing for Siemens Medical Solutions.

Radtke predicted that by 2010, installation of DR will approach 100% and demand for CR will steadily decline until CR is eventually phased out altogether, following the path of film.

"Emergency departments require a higher level of priority care," she said. "Because of its efficiency and increased image quality, DR is being purchased for EDs ahead of those systems being acquired for main radiology departments."

Receding costs are allowing DR to penetrate beyond academic and tertiary-care medical centers, moving into more community hospital EDs. Typically, the price of CR systems runs from $150,000 to $200,000, whereas DR solutions can cost from $350,000 to $500,000. Penetration is driven further as PACS implementations filter down to smaller hospitals. Still, DR is usually easier to justify clinically than financially, particularly in ED settings.

"It all depends of image traffic," Johnson said. "DR can be justified in the ED in terms of better patient care, but outside of areas like ICU or cardiac care, the cutoff is around 30 to 35 exams a day."

Western Baptist Hospital, a 300-bed facility in Louisville, KY, is one site where DR has made a positive impact on emergency department operations.

"All of our diagnostic x-ray rooms in the main department and the emergency department are now equipped with DR," said Robert Seely, director of diagnostic imaging.

Western Baptist's emergency department has DR portable capability as well as a CR reader, which is used for overheads for fluoro exams and some portable work.

Seely said the hospital is planning to open a totally digital outpatient center this month, the first facility in the region to use only DR technology. No CR is planned at this center. He cited several of DR's advantages. It is faster than CR, the technologist never has to leave the side of the patient from beginning to end of exam, and it is more cost-effective as a result of higher throughput.

The digital plates were installed about two years ago in both of Western Baptist's emergency rooms.

"We utilized three plates in the EDs - one in the table bucky, one in the wall bucky, and one that can be used tabletop," Seely said.

Seely said DR was accepted immediately by the technical staff and that the quality of images are superior to CR. Western Baptist has seen an increase of 23% in patient throughput since the installation of the DR plates, with no additional staff or rooms. The technology has also been trouble-free.

"It took a little time to adjust all the settings with our PACS, but since then, other than replacing one plate that was dropped on the floor, there haven't been any problems," Seely said.

For hospitals upgrading or expanding their radiology or emergency departments, purchasing DR technology has become almost a given, providing the opportunity to install the most efficient high-quality digital system available at little added expense, since the room is being replaced anyway.

"If you're ready to replace the room, DR is fantastic," Minnigh said.

Some DR units are designed to perform a full range of procedures - head, chest, skeletal, and extremity - in trauma or general radiology areas. Optional rail configurations permit one system to serve multiple trauma bays, improving workflow and reducing capital costs.

St. Luke's Hospital, a 393-bed facility in New Bedford, MA, chose DR during a recent $33 million ED redesign and radiology department upgrade. DR is now used in the ED for trauma patients and in the main radiology department for both inpatients and outpatients, said Eliane Cabral, St. Luke's radiology manager.

"The ED renovation replaced two conventional x-ray rooms with one digital room, which now handles the volume that went through the two rooms with no significant delay in turnaround," Cabral said.

Footprint savings are one of the prime financial advantages of DR.

"It is typical to see a high-volume hospital reduce the number of rooms by half when utilizing DR technology," Helbig said.

Another major financial advantage of DR is found in increased technologist productivity, particularly valuable during a technologist shortage. The technologist using DR conducts an exam, reviews image quality, and approves the study without leaving the imaging room. Technologists save time by not needing to handle cassettes.

"Space savings, combined with productivity benefits, provide an excellent way to justify the higher cost of DR imaging rooms," Helbig said.