Continued IT evolution boosts teleradiology

Nighthawk teleradiology is fraught with potential technical complications. Radiologists reading for an after-hours service may be scattered around the world, interpreting imaging studies during the day that were performed thousands of miles away during the night.

Group practices and hospitals that use their services require rapid response to address life-and-death emergency room decisions. The workload must be distributed evenly between staff and offsite radiologists who hold the appropriate state licensing and hospital certification. Redundant systems should optimize the nighthawk service's reliability. The Internet connections that hold these networks together must ensure patient privacy as defined by the federal Health Insurance Portability and Accountability Act. Software and technical strategies must fend off software viruses and human intruders.

These requirements place a heavy burden on information technology. Clinical acceptance and financial profitability for nighthawk teleradiology depend on exceptional IT, according to radiologists who specialize in this type of work.

"It is a crucial part of the practice," said Dr. Sean Casey, CEO of Virtual Radiologic Consultants in Eden Prairie, MN.

The high cost of employing radiologists requires companies like VRC to break new ground in high-volume remote interpretation, he said. Technology must allow the remotely based radiologists to perform as productively as their hospital counterparts.

"To present a competitive job package for our radiologists, we have to compete with the efficiency levels of onsite radiology," he said. "That requires us to achieve local area network-level performance over a wide area network."

Nighthawks accept new customers only when the systems and personnel are in place to maintain a 20-minute response time or less, according to Chris Huber, chief technology officer of Nighthawk Radiology Services in Coeur d'Alene, ID.

The company has emphasized in-house software development. Its seven software programmers developed AutoRAD, a proprietary radiology information system. AutoRAD distributes the work evenly among the staff while directing studies to radiologists who possess the appropriate credentials to perform the interpretation, said Jonathan Berger, vice president of sales and marketing.

"We can develop tools customized to the realities of workflow that only we understand," Huber said. "No off-the-shelf RIS product can be tweaked to truly meet our needs."

Reliability is essential for providing uninterrupted service. Remotely based radiologists can't temporarily switch to reading film because of a faulty PACS, Casey said.

VRC and Nighthawk claim a nearly perfect 99.9% uptime. Since establishing a global reading center in Sydney, Australia, in 2000, Nighthawk has lost only two hours of service to 300 hospitals around the world. The incident stemmed from a fire that forced an evacuation of the building, Berger said.

"We invest heavily in protecting against possible causes of outages because we don't have a fallback position," he said. "Teleradiology is our only business."

One way to assure redundancy is to deploy the radiologists reading for the service to sites around the world. VRC's radiologists practice in about a dozen sites in North America, Europe, Australia, and Asia, said Brent Backhaus, chief technology officer. When radiologists in New York and Boston were knocked out of action during last August's East Coast blackout, colleagues elsewhere picked up the slack.

VRC's central data center features backups for every key component, he said. Two separate power grid feeds (see figure) supported by a backup diesel generator and batteries provide a fail-safe source of electricity.

The firm's routers and servers reside in the same room as the Sonet Ring communications gear of a major Midwestern telecommunications company. The regional headquarters of several telecommunications companies are located in the same building.

A Sonet Ring is a high-speed Internet backbone loop that encircles large cities. Its proximity to this key component speeds up VRC's Internet connection considerably by eliminating the need to work through the local loop and the local service provider.

"We can connect our systems directly into the Internet's backbone," Backhaus said.

If a problem arises in the environment where VRC operates, the telecommunications company's best engineers will be called in to find a solution, he said. And the setup is scalable because, as the Midwestern hub for Internet connection, the resources in the room will grow to meet the entire region's demand.

ROBUST INFRASTRUCTURE

A robust network infrastructure is essential for several reasons, according to Huber. Having applications customized to the workflow has enabled Nighthawk to assure report accuracy while improving turnaround. The ability to transfer images in a secure way over the Internet cost-effectively serves as the underlying economic engine for Nighthawk.

"It is one of the key drivers that enables teleradiology to be performed half-way across the world," he said.

DICOM, the radiology-inspired software standard, has helped simplify the design of systems that transmit images using the Transmission Control Protocol/Internet Protocol. Huber considers TCP/IP the backbone of the Internet because of the way the application support services are transmitted over it.

"DICOM sits on a known Internet standard (TCP/IP). It doesn't have its own proprietary transmission protocol. This has allowed the Internet to be utilized to transmit these images," he said.

Virtual private networks (VPNs) capable of inexpensively protecting clinical images and patient information during Internet transmission is another important enabling technology. Cheap but sophisticated software encrypts data before transmission and unscrambles them after delivery, said Dr. Eric Trefelner, president of NightShift Radiology in San Jose, CA.

The DICOM standard and Internet technologies provide an element of predictability in an otherwise disparate environment. The 180 hospitals that receive nighthawk services from VRC vary greatly in size, location, and expertise, according to Backhaus.

Although most of them now have access to broad-bandwidth T1 lines for Internet communication with their nighthawk provider, some have yet to set up a local area network for their radiology departments, said Steven Runyan, an IT installations specialist with NightShift Radiology. In such cases, Runyan creates a LAN and connects it to NightShift's wide area network.

Most large hospitals have established networks and PACS, so the question is how to connect with their infrastructure, Runyan said. A hospital's security policies determine how he may proceed. Protecting the integrity of the hospital's firewall is key. Some hospitals allow NightShift to operate on their LAN. For others, the teleradiology company's computers are positioned in a so-called DMZ, a neutral space between the hospital's and vendor's firewalls.

"The setup involves a lot of interfacing," Runyan said. "We make the hospital feel comfortable that we are not invading their security, and we take care that it can't invade ours."

Because a nighthawk's WAN can connect with hundreds of hospitals, its administrator must remain alert to problems arising on any one of its clients' systems, said Dave A. Peyton, NightShift's network services manager. A viral outbreak at one hospital can quickly spread to infect all the hospitals in the network.

"It is important to know what kind of traffic is flowing across your network. Your virus scanners should be up-to-date," Peyton said.

VIRAL OUTBREAKS

The Blaster Worm and Lovesam viruses in 2003 infected at least three hospital networks that receive teleradiology support from VRC, Backhaus said. One infestation persisted for two days, forcing VRC to suspend services to that customer to protect its other clients.

Huber updated Nighthawk's operating systems with software patches supplied by Microsoft to address the Blaster Worm and Lovesam epidemics. Minor viruses have occasionally broken through, but they were eradicated before causing damage.

A well-maintained firewall and VPN protection keeps hackers at bay, he said. The systems allow VPN connections to be created only when passwords are entered in a precise sequence and then authenticated. Sessions are negated if the correct conditions are not met. VPN tunnels are not allowed to form. This doesn't mean that potential intruders don't look for weaknesses.

"Everyone gets sniffed on the Internet," Huber said.

Security will remain a key issue as nighthawk firms look to the future. The companies have until April 2005 to comply with final HIPAA security standards published last year. Nighthawk officials expect their company to be one of the first to have formal policies and procedures for the privacy standard in place. An internal assessment is planned to determine what needs to be done to meet the security requirements, Huber said. Although the rules appear to provide considerable room for interpretation, Nighthawk's stance favors full compliance to capitalize on the framework HIPAA provides.

"Documenting and meeting the requirements of the security standard is vital in 2004," he said.

HIPAA compliance is also a priority at VRC. Additional emphasis has been placed on following rules related to the mandatory encryption of patient information that could be intercepted as it moves between networks, Backhaus said. The firm has already established patient confidentiality agreements with its customers. It was advised by legal counsel, however, that business association agreements governing patient confidentiality with its vendors are not necessary.

Scalability is also a key issue, considering the phenomenal growth that nighthawk firms have experienced. Nighthawks' customer base grew 25% to 400 hospitals in the final five months of 2003, Berger said. The company plans to add eight radiologists to its staff this year, for a total of 30, and it will open a new reading center in Zurich, Switzerland.

VRC has grown threefold since Backhaus joined the firm in March 2002. Its monthly imaging volume increased 7% to 17,000 per month for the final four months of 2003, according to Casey. The company has purchased new servers and has installed load balancing capabilities in anticipation of additional growth. Order entry has been automated, and a new call center has been opened in Minneapolis to facilitate communications between customers and staff.