By Mark Bowen and Jon Hamdorf

Mark Bowen, Perceptive Software

Mark Bowen, Perceptive Software

The Vendor Neutral Archive—better known as VNA software—has been one of the fastest growing technologies in clinical imaging in the past few years. Analysts predict strong growth for this market through 2017. Early adopters are beginning to realize the value a VNA solution can bring to the healthcare organization. The challenge is that the role VNA was originally cast to play in healthcare has grown dramatically. Yet, we are stuck using a term that does not accurately represent the latest advancements in this diverse platform for medical content management.

The irony of the VNA acronym is that most people focus on the “archive” capability as the primary driver of the technology, when in actuality the archive component is only a small portion of the overall value a VNA can bring to a healthcare organization. Why? The vendors selling VNA, the market describing VNA, and the organizations buying VNA bought into the slogan of “Taking the ‘A’ out of PACS with a VNA.” We all know that picture archiving and communication systems (PACS) are departmental solutions that typically provide viewing, archive, workflow, and worklist components. Assuming a VNA only removes the archive and provides no additional value sells modern VNA solutions short. This article provides suggestions for new ways to think about the dimensions of a VNA platform as you plan for and evaluate solutions.

V” for “Visibility”

Jon Hamdorf, Independent Imaging Consultant

Jon Hamdorf, Independent Imaging Consultant

Visibility is one of the prominent problems in medical imaging today. Departmental PACS are good at presenting images that originated organically, but not good at providing visibility to departments outside their own. In PACS’ defense, it was never designed to perform this service. VNA technology, on the other hand, was intentionally architected to be a centralized archiving asset for use by diverse departmental systems. As VNA technology has advanced, industry leaders realized that federation capabilities are key not only to storing images but also to locating, retrieving, and delivering images to consumers, physicians, radiologists, and other constituents. For the best efficiency and results, it is essential that your VNA solution is able to federate across multiple departmental PACS systems and provide visibility to a variety of stakeholders across and beyond healthcare enterprise boundaries. This capability should be available on day one of a VNA installation, before any data migration is performed, and should be utilized as new systems are brought online through acquisitions and mergers.

Visibility also assumes a VNA platform can deliver any images from any system to a viewer for an end user to consume in a meaningful way. “Meaningful” means that: 1) the image can be opened/viewed; 2) the image has the appropriate metadata displayed to identify the patient in the context of the viewing experience; and 3) the necessary prior images of the case are available for reference. This drives home the point that there are even more fundamental capabilities every VNA must perform: tag mapping/tag morphing and pre-fetching. These functions are critical, especially considering that: 1) patients may have different MRN numbers across a healthcare affiliated network; 2) patient images may be from systems that require proprietary metadata tags to be visible or hidden in order to be displayed; and 3) patient images may be so old (based on retention policies) that required metadata tags don’t exist. Your VNA software should be able to solve these and other similar problems for your enterprise.

“N” Is for “Neutrality”

Most in the VNA community would agree that this letter of the acronym represents itself well. To be truly neutral, a VNA should be capable of storing images from any DICOM-based system. While we agree with this sentiment, it is radically incomplete because there can still be problems at the storage tier, at the viewer tier, and with non-DICOM-based systems. Storage neutrality means the VNA can abstract itself from the storage tier and enable the healthcare organization to use any storage vendor or type  (including cloud) that is available, accessing the storage infrastructure through published APIs rather than proprietary interfaces. For business continuity and disaster recovery systems, the healthcare organization can leverage the full value of the VNA and storage tiers by enabling the VNA to replicate metadata and the storage tier to replicate the image pixel data. This not only provides an optimized replication model versus an additional DICOM C-Store command but also ensures a reliable delivery method with confirmation that the study and images were successfully stored in the backup or DR system.

Neutrality must also exist at the viewing tier. Even with the growing popularity of enterprise viewers in the imaging market, every organization will need multiple viewers to support the differing workflows and requirements of the attending physician and the radiologist. Radiologists will need more complex toolsets and more advanced visualization capabilities, such as dual monitor capabilities, than other physicians. This flexibility also can help with recruiting and retaining radiology talent by allowing multiple viewers based on personal preference.

Neutrality in source systems is essential to an organization’s success in implementing an enterprise imaging strategy. A VNA must demonstrate how it not only can serve as an intelligent storage layer for DICOM images but also have functionality to support a broader set of imaging content—scanned documents, digital photos, video, etc—and the capability to store these assets in the originating format. It is critical that this content is not changed because the departments accessing it must be able to view the content in its original form, in the originating system, whether this is accomplished via DICOM, XDS, Web service, or other standards-based approach.

“A” Is for “Architecture”

As with any mission-critical application, the architecture can be the key to success or it can be the weak link in the overall technology strategy. To gain the most from your VNA solution, it must support a distributed, grid-based model and manage a spectrum of business and clinical content. The ability to support edge devices at remote sites and vertical and horizontal scalability is essential as images become larger and image volume grows. Architecture is your insurance policy against a decision that may be actively made (such as acquiring or partnering with an outside organization) or forced (such as government mandates and health policy legislation).

Remember that both PACS and VNA bring value but serve fundamentally different roles in the healthcare organization. Good luck in your quest, be wary of imposters, and keep your VNA and PACS evaluation processes separate. Visibility, neutrality, and architecture let you expand the definition of VNA as you consider a medical content management strategy for your enterprise.


Mark Bowen is Senior Influence Marketing Strategist at Perceptive Software based in Lenexa, Kansas. Jon Hamdorf is former Director of Global VNA Solutions for Perceptive Software and currently an independent imaging consultant.