Novel solutions overcome display and use drawbacksWireless PACS represents the ultimate in flexibility, response time, and productivity. Unshackled from wired terminals, physicians would be free to move to patients' bedsides and
Novel solutions overcome display and use drawbacks
Wireless PACS represents the ultimate in flexibility, response time, and productivity. Unshackled from wired terminals, physicians would be free to move to patients' bedsides and through the hospital or clinic, yet never be more than a click away from patient data and images. But the path to this future is littered with obstacles. Low-resolution displays on handheld PDAs (personal data assistants) fall far below current standards for diagnosis. The narrow bandwidth of wireless networks is antithetical to the increasingly fast pace of medicine. And modest adoption of PDAs could constrain acceptance.
The first steps toward meeting these challenges, however, are already being taken. With them has come the realization that obstacles to the adoption of wireless PACS may not be as formidable as had been imagined.
At the RSNA meeting, two companies displayed handheld systems optimized for radiology. Imco Technologies of Pewaukee, WI, introduced a line of lightweight wireless products in three configurations: One slips easily into the pocket of a lab coat. Another is somewhat larger but still weighs only 6.3 ounces and is 5 inches wide. The third is a tablet PC.
All three run on the latest Windows software, providing them with the capabilities of a standard laptop. Image resolution is low-240 x 320 pixels-compared with PACS monitors, which generally offer 2048 x 2048-pixel resolution. But the Imco products have a zoom feature that allows the user to target specific regions of interest. Wireless advantages include e-mail, access to patient data contained on radiology information systems, and an Internet browser.
Mark Schwartz, Imco president and CEO, envisions radiologists using the devices to display images to patients and their families, as well as to referring physicians. They might also use them as review devices to refresh their memories about specific cases when computer terminals are not available.
Siemens Medical Solutions used the RSNA meeting to launch a wireless tablet computer that runs on standard portable PC software. An electronic magnifying glass built into the MagicWeb tablet allows operators to view regions of interest more closely, enabling them to measure asymmetrical abnormalities, for example, and to compute angles. It has the same capabilities as workstations for image manipulation, windowing, and other functions, said Henri "Rik" Primo, director of clinical networking for Siemens. Radiology reports, laboratory results, pathology findings, and medication lists can also be viewed on the wireless device. Primo sees the devices being used in the emergency room, operating room, and referring physicians' offices.
Schwartz and Primo stressed, however, that their devices require a wireless infrastructure with a series of access points and network standards that are compatible with the hospital environment. This may limit the utility of the products, the two executives agreed.
The MagicWeb electronic tablet, for example, can receive and transmit data at 10 MB per second. Theoretically, throughput on today's wireless local area networks is 11 Mbps, but environmental factors, such as the distance between portable computers and network access points, restrict wireless networks to about 7 Mbps, said Dr. Saji Salem, director of the Health Insurance Portability and Accountability Act (HIPAA) Solutions Group at Silverline Technologies, an international e-business and integration services firm based in Piscataway, NJ. Actual speeds on most wireless hospital networks fare much worse, Salem said, usually reaching just 14 to 28 Kbps-about 4000 times slower than the 100 Mbps hardwired Ethernet connections to which physicians are growing increasingly accustomed.
Because of this weak link in the wireless chain, physician response to the bevy of handheld medical solutions addressing critical care monitoring, e-prescriptions, scheduling, and the electronic medical record has been mixed. Some early adopters have implemented a host of wireless applications, but most physicians have approached the wireless world with caution.
In radiology, where high bandwidth and display resolution are critical to the efficient handling of images, skepticism is especially valid. But solutions to both may be hanging on the walls of the University of California, Los Angeles Medical Center. Physicians there use handheld PDAs to drive flat-panel monitors mounted on hospital ward walls. The PDAs serve as identification devices as well as navigation tools for selecting patient data and manipulating the displayed images.
"We're taking the 'any image, any time' mantra to the next level," said Ric McGill, PACS application manager at UCLA Medical Center, whose system was displayed at the RSNA's infoRAD. "We're getting rid of the view boxes up on the clinician floors and using the handheld device as a network appliance."
UCLA engineers have taken the front end, or work list, from a fully functional PACS and put it on the handheld, McGill explained. This work list provides access to all patient data otherwise available to the physician on a hardwired PACS. It serves as a key to the patient data and is updated every time the physician syncs the handheld with the system.
Standing in front of the flat-panel monitors, which have replaced light boxes on the UCLA Medical Center walls, the physician requests data using the handheld by clicking on a patient name. The PACS retrieves and displays the requested image on the flat panel, simultaneously delivering the report for display on the handheld. The user can also access the HIS/RIS.
"You have a fully functional workstation," McGill said. "Anything a radiologist can do at a workstation in the radiology department can be done on the flat panels with the handheld."
The UCLA system has advantages even beyond the obvious improvements to flexibility in data access, according to McGill. Since only a clinician with a handheld can interface with the flat panels, the chance of virus contamination from infected MP3 or games downloaded by system staff is dramatically reduced or eliminated. Security officers may also find the system attractive. Unlike 14 x 17-inch film left unattended on a light box, sometimes all day long, the flat panel launches a screen saver that can be canceled only with a duly authorized handheld after 30 seconds of inactivity.
Regardless of technological capability, however, physicians must be open to its use, and that day may still be a ways off. Fewer than 1% of physicians in the U.S. use handheld wireless devices for medical transactions, according to W. R. Hambrecht.
"Wireless applications in imaging present various technical challenges, so adoption has been limited," Salem said. "But when the technology's ready, physicians will love going wireless. Think about using a mobile device to order a CT scan and then being alerted when the image is ready."
In an age when information rules and speed of delivery can determine success, wireless PACS is a near certainty. The only question is when.