Like all equipment, a picture archiving and communications system (PACS) has a life cycle. Accordingly, a PACS is purchased with the understanding that, eventually, the end point of its life cycle will be reached; then—or perhaps well ahead of that sad occasion—you will replace the wheezing and sputtering system with something new.

However, before the old PACS is replaced with a new platform, the unit tagged for decommission must be mined for the many images contained therein. The data extracted from the legacy PACS must then be loaded into the replacement system. And rare is the migration of image data from one PACS to the next that is problem-free.


The process of migrating data requires forethought, starting with a decision about exactly what is and is not to be migrated. Some PACS owners elect to move everything in the old archive to the new one. Others, like Phoebe Putney Memorial Hospital in Albany, Ga, are more selective.

“We’re still migrating data, and the way we’re doing that is by grabbing from the legacy system the complete set of prior images in a patient’s electronic folder the first time a physician has need of them,” says Ron Fraser, RT, radiology administrator, who explains that this approach saves space in the new archive by keeping out images of patients no longer under the care of physicians affiliated with the hospital; instead, those never-summoned images will remain with the old archive but entirely accessible via query from the interfaced new PACS should they some day be needed. “Once an image folder is brought across, it’s no longer stored in the old system’s archive. It will be automatically made part of the new PACS’s storage environment.”

Cost, of course, is a factor. Allina Hospitals and Clinics in Minneapolis estimates it is spending around 40 cents (the national average) to move each prior study to its new multi-facility, enterprise-wide PACS. Included in that sum is the cost of time and manpower necessary to perform the premigration validation of stored data, reports Rebecca Engstrom, Allina’s IS Lead Business Analyst for the Enterprise Medical Imaging.

Validation is crucial because dirty data may render some images unretrievable by the new system, or can lead to retrieval of the wrong studies. The latter is most prone to occur as a result of data having been entered originally in the old PACS without benefit of Modality Worklist, says Ed Petrella, MD, president and CEO of South Jersey Radiology Associates in Voorhees, NJ.

“A certain amount of image files will contain demographic data you can’t be sure about because it was entered manually,” he says. “For example, an image might be identified as an exam conducted on a patient named Susie Smith. But your database might also include records for a Susie A. Smith, S. Smith, Mrs Susie Smith, Ms Susie Smith, and countless other variations. Are they one and the same person? The only way to know conclusively is to go in and reconcile by looking at each entry individually.”

John Goldbeck confirms the point. He is a systems analyst in the IS/IT Department of Mercy Medical Center, Baltimore, where they are midway through a major migration effort: “Complicating matters for us, our radiology department’s PACS had been supporting an orthopedic surgeon whose practice generates a number of images—and the medical record numbers assigned by that office did not always match the medical record numbers in our HIS-RIS. We solved the problem by using special software to identify and quarantine records originating with the orthopod’s office. We knew that any record coming from there would have to go through a process of being matched against the records in our HIS-RIS so that those at variance could be cleaned up, and, going forward, we’d have only a single medical record number for each patient.”

At Allina, the task of validating old data was more complicated because the organization planned to continue using its legacy system (properly, systems plural: Allina would be stepping up from a number of scattered stand-alone mini-PACSs).

A Workflow Redesign Opportunity

With the arrival of an up-to-date replacement for a legacy PACS, an imaging department or center is presented a golden opportunity to significantly redesign its workflow.

Ron Fraser, RT, radiology administrator at Phoebe Putney Memorial Hospital in Albany, Ga, says he can think of no circumstance in which an enterprise would not want to avail itself of such an opportunity.

“It’s an excellent time to look at eliminating steps from the workflow,” he says. The move-up PACS delivered to South Jersey Radiology Associates, Voorhees, NJ, paved the way for just such a workflow makeover that included integration of that system with the enterprise’s RIS.

“When we’re all done with this process, we’re going to have a common desktop that will allow us to have RIS and PACS—two separate systems—operate as though they were a single system,” says Ed Petrella, MD, president and CEO. “That will be a huge benefit; it will greatly increase our productivity.”

At some point soon, the radiology department of St Peter’s Hospital in Albany, NY, will make a giant leap toward the fully electronic environment it has long sought but could not quite achieve due to the limitations of its legacy PACS, now being replaced. But even with the new PACS, 100% filmlessness remains a way off. So, to make things more efficient in the interim, radiology has contracted with a vendor to maintain at an off-site location a mirror of the film filerooms (St Peter’s Hospital has four). As older images on film are requested for comparison purposes, they are retrieved by the vendor, digitized, and then fed via virtual private network connection to the new PACS at St Peter’s Hospital.

“This prompted a workflow redesign on our part so that we could in a timely manner request images from our vendor and then make sure the received electronic versions would be routed to the appropriate radiologist for reading,” says Ed Vining, RT, administrative director of medical imaging.

The workflow redesign inspired by the introduction of enterprise-wide PACS at Allina Hospitals and Clinics in Minneapolis was a worthwhile exercise, says CIO Rebecca Engstrom.

“Users at the various locations where we had our numerous mini-PACSs installed walked us through, step by step, their routines for getting work done so that we in IT could understand the workflow patterns in radiology,” she says.

Vining notes that, while workflow can be redesigned relatively rapidly on the drawing board, implementation is another story entirely. “People are slow to embrace changes in the way they perform tasks, even if the new way makes the work easier or faster,” he says.

Phoebe Putney Memorial Hospital has attempted to overcome the objections to change by making redesigned workflow seem less like a top-down initiative.

“We’ve taken input from a variety of sources, including the users themselves,” Fraser says. “We’ve tried to get everyone to stop and think about why we do things the way we do. In many instances, it turns out things are done certain ways without any real justification—they’re just comfortable habits that people slipped into over time.”

Allina’s Brad Messerschmitt says his organization encourages compliance with the new methods of working by means of education.

“It was hard getting our people to rely on Modality Worklist when, for years, they typed everything in by hand, so we started a daily audit of the migrated archive to see who wasn’t using Worklist,” says Messerschmitt, systems integrator. “For those we identify as not using it, we then provide education about the benefits of Worklist. We also give them hands-on training in its use. Once they see how simple it is and how it speeds things up, compliance usually improves.”

—R. Smith

“We wanted to keep some of those old mini-PACSs operational for use as the viewing application, with the new enterprise PACS serving as their long-term data repository,” Engstrom says.

Engstrom indicates her department attempted to validate data by cross-referencing image records with the aid of match-establishing criteria, several sets of them. One of those sets aimed to produce matches was based on patient name, date of birth, and corporate identification. Another attempted to do so using only name and corporate ID, while a third relied on name and date of birth.

“Matches then were assigned a level of confidence,” she says. “A high level of confidence meant the data were valid and we wouldn’t have to do anything furthur with them before migrating them over.”

Those data that earned lower levels of confidence were routed to a quality-control workstation for manual modification in an effort to bring them into comportment with the hospital’s standards. Once that chore was completed, the data were migrated to the new PACS, Engstrom says.


After validating the data, the next step is their extraction and relocation. To be settled up front is the matter of how much data to migrate in any single batch.

“A concern for us,” Goldbeck says, “was the effect the migration of archived data might have on the network. We worried that, with so much data moving over the lines at once, there’d be a reduction in performance. We wanted to avoid that happening, or at least minimize it as much as possible, so the strategy we adopted involves performing the bulk of data migration during off-hours—7 PM to 7 AM—when traffic across the network is typically at its lightest.”

Notably, in any mass movement of data from an old archive to a new, some images and text will fail to make the crossing, cautions Ed Vining, RT, administrative director of medical imaging at St Peter’s Hospital in Albany, N.Y. The causes of such failure can be hard to pinpoint, but the most probable culprit is corrupted data.

“We had about 700 exams that we couldn’t migrate because of corrupted data files or some type of damage to our archive disks,” Vining says.

For the 700 that refused to budge, a work-around was devised to retrieve the images from the old archieve to a new system workstation an intermediary computer capable of cleanly receiving them and then, from there, routing them on to the new PACS archive.

“In the end, there were only a handful we couldn’t migrate,” he says. “Fortunately, these were older studies for which there’d be little if any demand.”


Another big challenge revolves around the need to keep radiologists fully productive during the migration process, which—if care is not taken—can lead to workflow bottlenecks.

“Our productivity-protection strategy was to create a completely separate migration server so that we could literally transfer the data offline and, in so doing, not disrupt workflow,” Petrella says. “The separate server is where we performed all our data validations and reconciliations. Afterward, we transferred the data to our new PACS.”

“We started migrating in this manner about a month before our go-live date and had 9 months of the most current data on the new system at the end of those 30 days. During that period, fresh studies were simultaneously written to both the old and new archives so that the radiologists could continue to work even as the replacement system was being populated with data and made ready for use.”

Petrella says the handoff began on a Saturday afternoon while the offices were closed for the weekend. Radiologists returned at 8 AM Monday and picked up where they left off, the only difference being they were working with a new PACS.

“It was a pretty seamless transition,” Petrella says.

Had Petrella’s practice instead made the switch during the workweek, go-live would have been preceded by some hours or days of image inaccessibility on either the old or new platform or both. A period of transitional darkness is typical. But not for Allina.

According to Brad Messerschmitt, Allina systems integrator: “We didn’t completely remove the viewing capability of our legacy PACS until the new system was fully operational and fully able to query and retrieve data from the legacy PACS. In this way, our radiologists could access data in both systems from a single workstation, and as a result never experienced any downtime—they at all times had access to all images. “


Many radiology enterprises find the process of moving from one PACS to another daunting enough that they hesitate to undertake it without the help of a migration support vendor.

“Having a trusted vendor to assist us in our effort was important,” Petrella says. “The vendor worked with us to develop a blueprint for how the migration would occur, and they followed it closely.”

The PACS migration vendor did most of the heavy lifting, so Petrella’s in-house IT staff could focus on other urgent tasks not directly related to the changeover.

The heaviest lifting in a migration is usually the data validation. As such, Vining thinks it a fool’s errand to attempt it alone without the help of a reputable conversion vendor, no matter how crack an IT staff one might possess.

“You really need to approach this process through a team effort, and a key part of the team will be your vendorsthe PACS vendor or vendors as well as a migration vendor,” he says. “It’s the kind of project that is complex enough that you need good teamwork and coordination across the board.”

Engstrom and Messerschmitt agree with Vining that teamwork is essential, but disagree with him on the extent to which reliance on an outside vendor is necessary. Allina’s dealings with a migration vendor were mainly confined to buyin a copy of the company’s software and the obtaining training in its use so that Engstrom’s team could execute the transfer themselves, in-house.

“This approach gave us a lot more control, and guaranteed us more cooperation from our PACS conversion sites,” she says, indicating that those locations included four metropolitan and six regional hospitals.

Says Messerschmitt: “It’s a lot better to be able to proceed at your own pace and not have to rely on someone else.”

Over at Phoebe Putney Memorial Hospital, this is that organization’s first migration from an old to new PACS, yet the IT department there is confident of success.

“We’re confident because we’re starting with a new PACS that has a reputation for making migrations very easy,” says CIO Patty Massey. “I’ve talked to colleagues at other institutions who are users of this system—people who are my friends, not references the vendor gave me. Even those who are by no means fans of this particular PACS vendor have good things to say about the implementation and migration.”

While the word of those colleagues carried much weight with Massey, it was not enough to convince her the system under consideration could facilitate a smooth migration. So she arranged for the vendor to demonstrate retrieval of images from the old archive to the new.

“We saw it work, and we saw that it worked with little in the way of preparation,” she says.

Massey is confident of success too for the reason that her department is tackling the job in partnership with radiology.

“Our basic premise is that, as IT people, we don’t know much about radiology, and vice versa.” she says. “But, by partnering our expertise, pooling what we each know, we’re far better positioned to be successful.”

Rich Smith is a contributing writer for Decisions in Axis Imaging News.