Alan Winakor is president of Metropolitan Diagnostic Imaging Group, LLC, Garden City, NY. In describing what a picture archiving and communications system (PACS) does for the privately held organization owned by five radiologists, he says, "PACS cuts down our windshield time," making it unnecessary for a radiologist to drive to the facility where an image was acquired in order to read it. The group has its administrative offices in Garden City, but maintains four imaging centers in Garden City, New York City, Brooklyn, and Forest Hills. Each center offers a full complement of modalities, including MRI, MR angiography, CT, radiography, ultrasound, mammography, bone-density scanning, and fluoroscopy. To date, MRI and CT have been connected to PACS, with ultrasound a possible future addition.

Winakor describes the PACS as using a modified hub-and-spokes design in which each of the spokes is interconnected. The hub is the main server and data-storage area at the administrative center. Each imaging center has short-term storage that allows images to be read in an uncompressed Digital Imaging and Communications in Medicine format, with long-term medicolegal archives being held at the administrative center.

Each radiologist has immediate access to images at a local workstation, but staff at that location need not store any images. If a radiologist at one center needs to help deal with excessive workloads at other centers, or is called upon to consult with a colleague at another center, the images needed will all be readily available.

Winakor had been following the progress of PACS for some time because, as he says, "We had a number of radiologists in different locations, and, as radiology became more specialized, we wanted to be able to move the images to the radiologists, even though they might not be physically on-site." Winakor adds that what held him back was both the expense of the available PACS and the fact that they were not technically evolved enough to meet his needs. About 6 years ago, however, Winakor came into contact with AMICAS, Inc, Boston, which "represented a company that, finally, could provide the technology to support what we needed."

Winakor acknowledges that being among the first multisite centers to pioneer PACS created a steep learning curve and some growing pains. "With this system, we need one information specialist assigned to the hub site to manage the system," he says. "He can easily monitor what is going on at each of the locations, even though he is not there. He can send images out, receive them, delete them, and do a variety of other things, including making sure the security is in place and maintaining the server."

Winakor adds that a system like his can take a year or so to develop fully if it is to be unveiled all at once. Instead, he chose an incremental approach to PACS implementation, and he reports that AMICAS worked with his timetable. "A fundamental reason that we chose AMICAS was because it had a web-based system, but, to date, only a small portion of our system is web-based, and that is the part that allows our radiologists to view images at home," he explains. The organization considers web-based operations a goal toward which it is evolving.

There were, Winakor notes, three things that the group wanted to accomplish when it implemented the system. The first was to be able to move images to the radiologists, sending images seamlessly via T1 lines back and forth between any facilities. This has been fully accomplished. The system has been implemented on a wide-area network so that even if there is a failure of the local-area network, the radiologists can continue to operate locally. As an additional security measure, Winakor stores images on data tape off-site.

Although the main intent of the PACS was to shift work to the appropriate sites, Winakor's second goal was to complete the transition from film to digital imaging and render the operation filmless. Winakor says, "We have cut down on the volume of film used," and he expects to reach filmless status during the first quarter of 2003. The third goal is to send images and reports via World Wide Web to referring physicians. Winakor says, "That should be a great marketing tool." The arrival of a fully web-based PACS, according to Donna Laraia, the group's director of marketing, will bring "filmless images that, at a click of a button, can be instantaneously communicated anywhere." Radiologists in different locations, or a radiologist and an emergency-room physician, a specialist, or a patient's primary care physician can all receive the images simultaneously and can confer concerning what should be done. "Eventually, our referring physicians, instead of awaiting the delivery of film to their offices, will be able to access the images in their offices," Laraia says. "They will be able to print off the screen when needed, and there will be no storage problems."

This degree of image distribution would not have been affordable when PACS projects were first seen in the late 1980s and early 1990s, generally in large academic hospitals that could afford to take risks in information technology. Costs were not directly related to hospital size, so even a 100-bed facility could expect to pay $1 million or more for PACS.

An additional problem was that these initial efforts were strictly departmental solutions not readily transferable outside radiology. The early networks were not robust enough to support the technology needed for ubiquitous image distribution. Early PACS were expected to reduce film and staff costs, but they required significant capital investments (and, at times, extra staff).

AMICAS entered the PACS field in 1995, when Massachusetts General Hospital, Boston, hired the company to move images to a web-based technology. Using a combination of web distribution and teleradiology, AMICAS was able to foster the evolution of the necessary processes; today, the resulting system has approximately 1,000 users throughout the hospital and handles thousands of studies per day. AMICAS has retained the rights to this process (as intellectual property) and has worked to improve it continually.

The work at Massachusetts General Hospital also suggested another use for the process: sending digital studies from one hospital to another. Using a combination of teleradiology (with images transmitted over traditional networks) and selective web technology, Massachusetts General Hospital has been able to transmit images to facilities as close as the Boston suburbs and as far away as Greece and Turkey. It was this multisite hospital concept that led to the nonhospital multisite PACS application at Metropolitan Diagnostic Imaging Group.

While PACS technologies changed over the years, imaging modalities were also becoming more sophisticated. A CT study that once generated 100 images might, using today's multislice CT scanners, produce 1,600 to 1,800 images. Advanced information-handling capabilities are necessary if a facility is to manage this flood of data. Winokur says, "We got the PACS first and deployed our multislice CT scanners later. I cannot imagine trying to deal with these images on a film basis. It would have been very difficult, but just scrolling through the new CT images with the PACS makes it instantly better. The AMICAS system is quite capable of handling it, and we have had no problem in this area whatsoever."

Winakor also approves of the archiving protocols of the new system. "With the old methodology," he says, "we had to have two sets of films, and the film had to be manually retrieved. Now we just go to our database on the server and get the images we want back almost instantly." Image quality is the same as it is on film, but some of the digital tools available provide better access to the images. The user can magnify the image, change its contrast or orientation, and highlight different areas."

With the evolution of PACS, radiology practices have the opportunity to move forward and do things that film-based practices could never do. The tendency is to keep the same procedures with digital imaging that were used with film, but this cuts off new possibilities for improving efficiency and diagnostic precision. Just as multislice CT scans provide finer detail, filmless operation provides a chance to redesign inefficient processes and improve productivity. Important images can be pushed to the relevant locations at critical times, and the reporting process can be streamlined.

CONCLUSION

The volume of data generated by radiology is expanding more rapidly than Internet transmission speeds are increasing. As a result, AMICAS has chosen to focus on wavelet compression technology and on meeting the US Food and Drug Administration's requirements for image validation. Instead of being able to support only small communities of users and relatively limited numbers of images, AMICAS can support large communities generating hundreds of thousands of images. Because the AMICAS software is standardized to run on nearly any hardware, PACS costs are also approximately 50% lower than they would be for a proprietary system.

PACS is a rapidly evolving technology responding to rapidly changing conditions. It is an idea whose time has come, yet its development continues. From his perspective at a multisite imaging center, Winakor says, "We have not fully arrived, with our PACS, but we are confident that we are on our way."

Louis Hale is a contributing writer for Decisions in Imaging Economics.