Tuesday, December 1, 2009

Semi-neutral Archiving

"Vendor neutral archiving" is the current buzz-term from the 2009 RSNA meeting in Chicago. It is a requirement if an institution would like to have a single enterprise solution for all of its images. In most cases, additional sources of images after radiology are cardiology, surgery, endoscopy, as well as other specialties such as dentistry, and dermatology. Using an individual image archive for each department that generates medical images makes no sense. 

A single data repository for all medical images in an institution is driven, in part, by IT professionals who see this solution as achieving economies of scale for both physical infrastructure and administrative support. In addition, the increasing implementation of EMR technology literally demands a single source for image data. 

However, early experiences with trying to disconnect and isolate the archive component from the PACS have not always been easy or painless. Unfortunately, the IHE has not yet delivered a bulletproof profile, as the image manager and image archive do not yet have a standardized protocol and/or interface. Users have found that there is still proprietary information that is vendor specific in their archives. Also, archive performance has been reported also to be an issue. 

What should a system administrator do to prepare for transitioning their department to a shared, enterprise-wide archive? 

First, it is prudent to maintain the first archiving tier from the same PACS vendor. Images are still retrieved from this primary server, and retrievals for the first few days and/or weeks are served by this first tier archive. A copy can be sent to the vendor-neutral enterprise archive for distribution as part of the EMR. Image retrievals and/or pre-fetching of images after the roll-off date to the second archive (enterprise) tier (such as 1-3 months after implementation) will be from the enterprise archive. 

Second, a well defined interface specification, performance requirements and comprehensive acceptance testing should be part of the enterprise archive purchasing process. References from other sites who have implemented an enterprise archive using your flavor of PACS with that archive are important, too. 

One test I recommend conducting is to run a "compare" script. This will demonstrate that images are archived and retrieved in an identical fashion from both the PACS archive and the enterprise archive. Note that synchronization between tier 1 and tier 2 archives can be tricky, particularly when changes are made—such as modifying patient demographics—at one or the other archive level. Make sure that the DICOM standards that deal with Presentation States and Key Images are supported. 

Healthcare Information Technology Management, Part 4 of 4

Part four of a four-part series on healthcare information technology. The information found in this article can be used as part of a preparation program for the American Board of Imaging Informatics (ABII) Imaging Informatics Professional certification program, which awards the Certified Imaging Informatics Professional (CIIP) designation.

For further information on an extensive set of topics of interest to prospective CIIP candidates, please go tohttp://www.otpedia.com.


The backbone of Healthcare Information Technology (HIT) is comprised of physical and logical networks, servers, databases, and archives. These elements comprise the engine the drives the HIT enterprise. The design and deployment of these HIT components requires a thorough knowledge of the interaction of one with the other, the capabilities of each, the standards affecting their implementation, and a planned upgrade path for when current technology is eclipsed by future innovation.

Network Hardware and Software Implementation and Maintenance
Hardware 
A network is comprised of a variety of hardware devices. 

These include repeaters or hubs, switches, routers, gateways, and servers. In addition, depending on the speed of the desired network connection, different type of cabling may be used such as unshielded twisted pair (UTP), shielded twisted pair (STP), coaxial, or fiber optic. In some instances, wireless networks (wLAN) may also be deployed. 

Software 
As a healthcare IT professional you will be working with a number of operating systems. Microsoft Windows is the major operating system you will face, but the some systems also use UNIX and Linux operating systems. You may also be called upon to use DOS as a means of trouble shooting network problems.
  • UNIX: mostly for the back-end (servers)
  • Windows: some back-end, mostly for workstations
  • Linux: some view stations, some RIS systems
Diagnostic imaging IT administrators need to be familiar with operating systems because they are the most important program that runs in a PACS. 

An operating system (OS) runs the hardware and control interfaces and peripherals. In a PACS an OS is the system software responsible for the direct control and management of hardware and basic computer system operations, as well as running application software such as image processing programs and Web browsers. In general, the OS is the first layer of software loaded into computer memory when it starts up. 

Utility programs perform tasks that maintain a computer's health-hardware or data. Utilities perform:
  • File Management
  • Disk Management
  • Memory Management
  • Backup
  • Data Recovery
  • Data Compression
  • Anti-virus
Many PACS-specific utilities come with PACS products while others are available on the third-party market or as free open-source applications. 

Server Architecture 
There are basically four types of server architecture–mainframe, file sharing, client/server, and application server provider (ASP)–with variations and mixed environments common in healthcare IT. 

Mainframe architectures host all data at a central host computer. Users interact with it through a terminal that captures keystrokes and sends that information to the mainframe. 

File sharing architectures are where a server downloads files from a shared location to a desktop. The requested task is then run (both logic and data) on the desktop. 

Client/server architecture utilizes a database server to replace the file server. Employing a relational database management system (RDBMS), user queries are answered directly. The client/server architecture reduces network traffic by providing a query response rather than total file transfer. 

In an ASP-based architecture, the application is provided to users over a network and is accessed by users through a Web browser or client software provided by the ASP vendor. Medical billing, PACS, and archive services are some of the commercial offerings available with this model. 

IT Replacement Schedule Development
Planning for Obsolescence
Not matter what computer technology or software a healthcare IT administrator installs, there will soon be something faster or "better" soon. Obsolescence is a fact of life in technology. Planning for it is the responsibility of the healthcare IT administrator. 

Hardware is usually the slowest component to become obsolete; however, be aware that new software applications, such as 3D modeling, can accelerate hardware obsolescence. Generally, features such as extra memory and external drives can be added to extend the usable life of hardware. 

Software obsolescence depends on when vendors decide to add new features and upgrades and when users demand to have them. It is important to note that vendors will decide that they are no longer going to support older software versions, which forces many of their customers to upgrade to the latest iteration. 

Technology Lifetime
Recognizing that technology has a definitive lifetime is an important consideration when selecting a particular technology or format for deployment in a healthcare IT enterprise. 

For example, consider music playback technology. Wax cylinders gave way to 78 RPM disks, which were supplanted by 45 RPM, then 33-1/3 RPM records. 8-track cassette tapes were rendered obsolete by smaller-format cassette tapes, then records and tapes disappeared from the market with the advent of CDs. Of late, CD technology for music distribution and playback has been threatened by the explosive growth of MP3. 

The lesson is that there will continually be new developments in technology. Savvy healthcare IT administrators need to plan for the technologies of tomorrow by ensuring that their current deployments support accepted standards–ensuring that their data can be successfully migrated to new platforms. 

Moore's Law
Moore’s Law is an observation made in 1965 by the co-founder of Intel, Gordon Moore, that the number of transistors per square inch on integrated circuits had doubled every year since its invention. 

Moore predicted that this trend would continue for the foreseeable future. In recent years, the pace has slowed, but data density has doubled approximately every 18 months, and this is the current definition of Moore’s Law.