The transition to digital radiography necessitates new ways of managing information. It also requires new thinking about the power of today’s Web technology and how it can be harnessed to improve upon conventional radiography.
At St. Louis Children’s Hospital, more than 90,000 diagnostic imaging studies are conducted annually. The hospital is a member of Barnes Jewish Christian (BJC) Health System, the first fully-integrated health care system in the country to join an academic medical center with suburban, rural, and metropolitan-based health care facilities. It is also affiliated with Washington University School of Medicine.
Children’s Hospital was among the first to implement digital image acquisition with computed radiography, CT, and MRI. Significant capital dollars were invested in digital modalities made by a variety of manufacturers with the goal of increasing productivity and enhancing patient care. As these goals were realized, it appeared time to take the next step by implementing a picture archiving and communications system (PACS). Doing so would allow the department to further enhance productivity and improve its storage and retrieval process.
While the rate of PACS adoption remains small relative to the number of hospitals in the United States, the benefits experienced by those sites that have the system are many. PACS reduces printing and automates the collation and hanging of images, enabling radiologists to concentrate on interpretation and dictation. There are fewer lost films, image retrieval is virtually automatic whether on site or off, and images can be viewed simultaneously by multiple consulting physicians — again, regardless of location. As electronic medical record (EMR) usage increases, the radiologist’s report could be integrated with the patient’s images, and this could further be integrated with laboratory test results, billing records, and other patient data.
And, as opposed to the dumb terminals of the past, the workstations can be used by radiologists and technologists to access the Internet, bookmark Web pages or other online resources, and add them to the patient’s electronic folder. These features result in faster (and potentially more in-depth) diagnosis, greater throughput and efficiency, reduced costs, and improved patient care.
But these potential benefits can come with a hefty price tag. St. Louis Children’s solution was to install a software-only version of one vendor’s PACS. This software-only PACS worked seamlessly with our existing, multi-vendor hardware, providing us with the full benefit of PACS without necessitating an expensive and time-consuming change in hardware. The software-only solution enabled the hospital to complement existing hardware with the latest technology, extending its useful life and significantly reducing the overall cost of PACS implementation and ownership. Based on experience, the estimated cost will be up to 50% less than that of buying a traditional PACS system.
Integral to the success of this installation was the hospital’s committed information technology (IT) staff, which is well versed in the thin client, Web-based architecture on which our PACS operates. Due to its expertise and strong partnering with the vendor, the department was able to install the server and workstation software in less than 3 hours, using just four CDs. And because the software-only system does not require proprietary hardware, the IT department had complete freedom in terms of hardware purchasing, flexibility, maintenance, and service. It was able to use existing hardware that meets minimum specifications that would take advantage of the functionality of the software.
Another feature making the software-only installation such an attractive option is its innovative, next-generation server configuration. Legacy PACS architecture appends a Web browser to its dedicated servers, each of which is designed to perform only one specific function such as traffic, database, or archive/storage. To expand the system or upgrade the application’s capabilities, these single-function servers must often be replaced, leading to higher operational and capital costs during the life of the system.
Conversely, the software selected incorporates a Web-based architecture, featuring servers that are designed to perform multiple functions and are easily scalable. The software incorporates hierarchical storage management (HSM) into its operation, which provides a standard interface for the management of data independent of long-term storage. The HSM software is designed to move images from primary storage — the redundant array of inexpensive disks (RAID) system — to secondary storage devices, which may be another RAID or a digital linear tape (DLT) library. This system expansion methodology replicates and distributes the logical intelligence of the system across multiple hardware components, enabling users to perform their work as if the system were a single seamless entity. This allows the hospital to add multiple-function servers and workstations at its own pace without replacing the equipment already in use. New equipment is purchased only as needed. Benefits of such a system include optimized communication, simplified system integration, a flexible growth path, and automated software distribution and upgrades — all while reducing total cost.
Storage is also scalable, which is especially important to a pediatric hospital such as ours. Unlike other institutions that require that patient examinations be saved for 7 years, we must maintain our records for 26 years. With the software program meeting the industry’s standards for writhing storage to devices, the storage components can be purchased incrementally, allowing future technologies to be added to the system as they evolve without the need for software recoding. Therefore, storage can be added according to our own growth while incorporating the latest technologies along the way. Depending on the age and usage of the study, images are stored in either the RAID online or the DLT format deep archive as lossy (nonreversible compression) or lossless (fully reversible compression). After an examination’s final review, based on system preferences, data migrates from RAID to DLT following a least-recently-used algorithm written into the software rather than initial date of consultation. And, when retrieving images, there is no need for the user to know where the data is located because the system will automatically and immediately search and retrieve from both. This simplified retrieval process makes historical comparisons quick and easy to access.
Convenience and customization were also factors in our PACS decision-making process. Many of our pediatric cases involve long-term and large database comparison scans — MRI/CT modalities — and large teams of clinicians across multiple disciplines. These referring physicians, radiologists, pediatricians, surgeons, oncologists, radiation therapists, and other specialists all have different work schedules and styles and typically work at different sites. Therefore, it is imperative that the PACS architecture provides a platform for immediate access to patient information at any time, to any number of users, from any location.
To enable maximum flow of information, the PACS software invokes user profiles to give users access to examinations via any workstation within the network, whether on or off campus. Further, the user’s viewing preferences and display protocols engage automatically at the time of log-on, again, regardless of the workstation being used.
These features eliminate the limitations of legacy systems that require the auto-routing of images from a central workstation and workstation-restricted user preferences.
Although all neuroradiology procedures, CT, and MRI are reviewed and interpreted from monitors, 50% of the procedures are still being filmed. Once monitors are deployed throughout the neurology and neurosurgery sections, the neuroradiology division will be completely filmless.
Speed, Display Crucial
Speed and display options are crucial, and played a key role in clinicians’ acceptance of the new system. They can access an entire 460-slice MRI examination in just more than 5 seconds, displayed according to their personal hanging preferences. Then, they can choose any image in a series and quickly shuffle through the surrounding images using the mouse wheel. When they reach a slice of interest, all surrounding tiled images are reset in sequence relative to the selected slice.
The software-only PACS solution also allows users with other DICOM-compliant systems (including echocardiography, catheterization laboratory, and ultrasound) to access PACS. It is expected that a similarly constructed Web-based radiology information system (RIS) or EMR system could also access data directly from the PACS via true Web URL (uniform resource locator) protocols without the need for HL-7 or DICOM. The hospital is currently in the process of integrating PACS with our existing HIS (hospital information system)/RIS to streamline delivery and improve the quality of patient care.
The Web capabilities imbedded in the PACS also provide online upgrades, reducing costly workstation support and maintenance. In addition, it uses a standard Microsoft Windows and Internet Explorer (IE) interface so that its look and feel are consistent with most users’ past computing experience. The workstation’s desktop format is equipped with the standard IE tool bars, icons, and menus, making it familiar and user-friendly.
This functionality further improves productivity by minimizing any learning curves. In addition, through the use of the IE interface, the workstation automatically integrates with other Windows applications such as email and multimedia presentation software packages.
In selecting a cutting-edge technology like Web-based PACS, the PACS implementation team was hopeful, yet still leery of some of the failed promises of PACS in the past. Happily, the system has delivered on all the anticipated benefits. Children’s is presently reaping the rewards of these foundational features, which all legacy PACS are expected to migrate to in the future. Given our success to date, it is the hospital’s intention to broaden access to PACS images through additional software licenses and the incremental advantages this may bring.
Michael Albertina was director of radiology services at St. Louis Children’s Hospital, St. Louis. He is now director for radiology services at St. Louis University Hospital. Benjamin Lee, MD is a neuroradiologist at St. Louis Children’s Hospital.
Michael Albertina was director of radiology services at St. Louis Children’s Hospital, St. Louis. He is now director for radiology services at St. Louis University Hospital.
Benjamin Lee, MD is a neuroradiologist at St. Louis Children’s Hospital.
