Radiology Plus-Standardized Interfaces Open New Era in Sharing Images

Radiology information systems going 'plug and play'

The substantial cost of computerizing a radiology practice has kept many small practices from making the leap to an electronic information management system. But a ground-breaking newly debuted "open" interface—the behind-the-scenes electronic protocol that bridges the language gap between information systems—promises to ultimately lower that cost, enabling even the smallest practice to move into the computer age.

Even large hospital practices that are already computerized can benefit monetarily from the transaction profiles developed as part of the year-old project, titled Integrating the Healthcare Enterprise (IHE), says R. Gilbert Jost, MD, chairman of the Chicago-based Radiological Society of North America's Electronic Communications Committee. The new process precisely implements Digital Imaging and Communication in Medicine (DICOM) and Health Level 7 standards and will increase data and information accuracy and accessibility and reduce costs, he adds.

"Some companies have certain products in which 90% of the cost of implementing them is in building the proprietary interface," Jost says. With standardized interfaces such as IHEs, "obviously it is less costly to build the product and much easier for radiology departments to install it. We predict significant savings."

The IHE, a collaborative effort instigated by the RSNA and the Healthcare Information and Management Systems Society (HIMSS), unveiled the interface at the 85th Scientific Assembly and Annual Meeting of the RSNA Nov. 29 through Dec. 3 in Chicago. The RSNA demonstration showed 46 separate information and imaging systems using the new, common interface to operate in a highly integrated fashion. The project foreshadows a future in which radiology practices will no longer have to rely on expensive proprietary interfaces to enable their imaging modalities and information systems to communicate with each other and with the hospital's information system.

Another demonstration will be held at the HIMSS annual meeting in April in Dallas. The IHE-compliant information systems should be commercially available in the next six to 12 months.

"Before very long this will have a direct impact on even the smallest radiology practice because everyone is moving in this direction—toward an electronic approach to radiology," Jost says.

No Information System is an Island

In the project's first year, more than 20 different competing manufacturers banded together to develop a technical framework that defines common interface protocols that will enable their various products to communicate with each other without the need for elaborate proprietary interfaces that normally would have to be built separately.

"Computers will be able to communicate with each other regardless of the vendor," says Jost. "It's almost 'plug and play.'"

Here's one example of how the IHE interface works:

Patients present to the hospital registration area or in the emergency department and all patient demographics and necessary procedures are entered into the hospital information system (HIS). This information only has to be entered once and is recorded in a standardized format that the radiology information system (RIS) can access almost immediately. So, conceivably, a patient's information would be in the radiology department before he or she completes the walk to that department.

Once the patient information and the patient make it to the radiology department, staff there can access the patient information via the RIS and update it if needed. For example, the HIS information may only indicate that the patient is to have "a leg X-ray," and the radiology technician can specify which leg, or a radiologist can add more procedures to the growing work order for the imaging equipment. The patient's name and demographics do not have to be re-entered—eliminating the potential for errors such as name misspellings that could link images to the wrong patient. The RIS then communicates the updated information to the HIS if it is in a field that is needed by both systems.

At this stage, technicians using the RIS can schedule resources—staff, equipment, and exam rooms—for the patient's procedures, says Paul Helmuth, engineering manager in imaging for Kansas City, MO-based Cerner Corp., a clinical information system provider that is participating in the IHE project.

The growing modality "work list" is sent directly to the imaging equipment so it automatically knows which procedure to do to which patient and when. This ensures that the images taken are correctly identified as belonging to the patient, allowing radiologists to prefetch previously stored images taken of the same patient when needed to make a diagnosis. A technician merely has to confirm that the person who shows up at the exam room at the specified time is the correct patient who is scheduled for the procedure.

Interface Aids Radiology Billing

The modality sends a message to the RIS and to the picture archiving and communication system (PACS) when the patient's procedure is started and another message when it ends. This step is important for billing purposes, since it notes exactly which procedure was actually performed—not just what was scheduled—and how long it took. The imaging modality also notifies the PACS how many and of which type of images for that patient it will receive. If all goes well, the imaging equipment sends the images to the archiving system, which stores them. If not, the archiving system can flag the incident and kick it out into a "penalty box," where a technician must solve the problem—perhaps by querying the modality to see if it has any more images to send.

Once the images are safely stored in the PACS, the archiving system then sends a message telling the RIS and the imaging modality that the images for this patient are stored and available for viewing to anyone who has the appropriate access from any radiology workstation. For example, a radiologist can immediately query the PACS to see the images from any authorized RIS workstation. Notifying the imaging modality that the images are archived allows it to erase its local memory of that patient's images.

"That's a big advance," says Chris Carr, assistant director of informatics for the RSNA. "It saves memory and you don't have to have a human erase the images."

The electronic images are of "comparable quality" to the standard films radiologists have used for the last 100 years, says Jost. While they may not be of identical quality, electronic images easily can be manipulated in ways that improve their readability, such as by magnifying them or by increasing their contrast, he adds.

Communication Helps Prevent Medical Errors

The improved accessibility of more accurate patient data will "go a long way to providing better quality care" and will help prevent medical errors commonly caused by inaccurate patient information, he says. And it has the potential to expand teleradiology, which has primarily been used to communicate image information. "It opens up the possibility of communicating much more than that," Jost says.

Some elite information systems have proprietary interfaces that already offer a seamless flow of accurate information similar to what the IHE interface affords— if all components are made by the same vendor. "But that locks you into a relationship with a single vendor and all the uncertainties that go with that dependency," says Carr.

IHE allows radiology practices to mix and match components from different vendors and still achieve a high level of compatibility and connectivity without the hassle and expense of building a proprietary interface. "Interfaces are expensive, labor-intensive animals," says Helmuth.

And while complex proprietary interfaces can be built to bridge the communication gap between different vendors' disparate systems, there is inherent risk in relying on such custom-made interfaces. "The self-made solutions usually depend on one or two key people, and there is a lot of turnover in the industry," Carr says. "They can leave and you're left with a system that no one on your staff built and no one knows how to fix or maintain."

Debra Stenner, vice president of development for Burlington, VT-based IDX System Corp., an IHE-participating vendor, highlights another risk of relying on such interfacing between different vendors' systems: the dreaded update. She notes that one customer's information system was down for 13 hours because a vendor updated its PAC system and the interface that connected that vendor's system to IDX's RIS system no longer worked.

The IHE interface avoids problems like this, while "eliminating redundancy and filling in gaps in information," says Stenner, who is also on the IHE planning committee.

IHE in Years Two and Three

In year two, the IHE project will ask the standard-setting bodies to create standards for necessary communication activities that currently have no standards, so that the standards can be used as the basis for more standardized functions, Carr says. IHE will also concentrate on adding additional commonly defined functions for:

Standardizing the protocols for report management. IHE will create a structured reporting model and a standardized format for creating and storing patient information reports.

Handling major exceptions. IHE will create a way for the system to reconcile emergency trauma cases in which the procedures are done prior to entering the patient's name.

Making the "images available" message available to the HIS. IHE will create the framework that spurs the interface to notify the HIS—not just the RIS—when images are available for viewing and allow the images to be viewed from any appropriate station connected to the HIS.

Setting parameters for soft copy and hard copy consistency. IHE will implement the DICOM standards that provide consistency in the display of images across different platforms, monitors, and printers. For example, if an image looks best with a particular brightness, contrast, or gray scale, that information will be transferred with the image so these adjustments don't have to be made manually by the radiologist.

Creating a standardized message for querying the RIS. IHE will create a standardized message that any system could use to query the RIS to find a particular patient report or image. Obviously, this could pose patient confidentiality and security issues.

Standardized encryption procedures do not yet exist for this function, so addressing the potential patient confidentiality problems that come hand in hand with increased patient information accessibility will be an important issue for the IHE project to address in year three.

In the next six weeks, the planning committee is writing a detailed long-range plan for the project. The IHE will expand its integration goals to include health care information systems other than radiology, such as those in pathology, laboratory, and cardiology, Jost says. v

Editor's note: More information about the IHE project and its interface can be found on the RSNA web page at: