After years of relinquishing control of picture archiving and communication systems (PACS) data to vendors, VNAs finally put healthcare facilities back in the driver’s seat. And that’s also true of other types of healthcare IT data. VNAs also offer other important benefits, including:
- Automatic access to a patient’s full clinical history across all providers;
- Electronic medical records (EMRs) enriched with all patient images and reports – no matter what the department or source of image generation;
- The ability to upgrade to a new PACS from any vendor in just hours;
- Simplified and secure lifecycle management of the clinical images across the entire enterprise; and
- A platform to share and communicate data among enterprises as part of a health information exchange (HIE).
While definitions may vary, most experts agree VNAs should:
- Provide patient-centric storage;
- Support open standards;
- Manage varied content, including images, video, sound, treatment plans and other data objects;
- Provide the capability for query, storage and retrieval;
- Support multiple departments, enterprise and regional architectures;
- Maintain patient privacy and security through audit trails;
- Transcend upgrades and changes of PACS and allow PACS solutions to be interchangeable;
- Eliminate future data migration and/or conversion of data formats;
- Be hardware agnostic; and
- Be integrating the healthcare enterprise (IHE), digital imaging and communications in medicine (DICOM) and Health Level Seven (HL7) compliant.
The VNA: Standards-based storage at last
What truly distinguishes a VNA from an ordinary PACS archive is that it utilizes storage techniques, data formats and data-exchange methods for healthcare information by adhering to industry standards, independent of the application that created the data. With a VNA, such as TeraMedica’s Evercore solution, IT applications are no longer tied to physically addressed storage and communication with other systems through proprietary integration.
Underlying the VNA benefits is a consistent metadata format that enables identification of all data for a particular patient, wherever the information is stored on the IT system. This patient-centric data presentation eliminates today’s crazy quilt of costly, clumsy IT interfaces and homegrown workarounds that attempt to fill the gaps between incompatible IT systems. With a VNA, any application using the archive requires only a single point of integration to a standardized service for access.
VNAs typically include data from the health information system (HIS), radiology information system (RIS), PACS, EMR and information from numerous specialty departmental systems.
An anecdote for proprietary PACS data
Since diagnostic images and reports are among the most frequently shared information across the continuum of care, it is precisely the isolated and often proprietary PACS archive that poses a particular problem to hospitals – and to radiology departments that wish to upgrade to a new PACS application. The VNA provides an elegant answer with implications across the enterprise and beyond.
While DICOM was created as a shared data standard for medical images, many of today’s PACS problems are actually rooted in DICOM itself. One issue is that DICOM fails to fully specify the metadata tags (fields) used to identify and annotate data. Thus, vendors have been able to interpret and use the standard in myriad non-standard ways. Additionally, DICOM permits the addition of private tags, which will not read across vendors. It also allows relational data fields to remain empty, with negative consequences. In short, DICOM provides ample opportunities to keep data tethered to a specific application.
Further, the promise of an EMR enabled with DICOM images and related information is even more complex. This can require custom interface engines to link unrelated systems and possibly data transformation. It may even call for the duplication of entire archives. Interfaces are costly to create and maintain over many years, and they also can produce security risks and scalability issues. Data duplication multiplies storage and maintenance costs. In addition, imaging files are enormous and becoming larger – and therefore are complex, costly and challenging to share.
Moving all information to a truly standardized platform that is able to make the necessary translations between endpoint systems eliminates many of these problems. With a VNA, sites can share images across systems, migrate to a new PACS and manage data more easily.
Images beyond radiology
The benefits of the VNA do not stop with radiology – nor do the challenges faced by traditional PACS. Currently, a PACS is often called upon to store a growing variety of data – both DICOM and non-DICOM – from within radiology and elsewhere in the hospital.
DICOM data stored may include cardiology, neurology and other specialties. The departments that generate this data often have their own identification numbers, requisition systems and even accession numbers that all must be reconciled and managed within the PACS just to create an integrated record in this single application.
Radiologists are increasingly adding non-DICOM data objects, such as scanned prescriptions and reports, to the PACS archive. Additionally, the data contributed by other departments may not be in DICOM format.
Without an accepted metadata management standard to help reference this information to a specific patient, this data also remains tied to the PACS as well as to the department that created it. With VNA standardization, management becomes far simpler and sites have the freedom for cross-application use.
Departmental specialty systems
Whether or not information from the other specialties is managed in a PACS, naturally, it resides somewhere within the hospital IT system. If archived in a separate application with even more department-specific formatting, the difficulties of introducing it into any standardized system or an EMR are even greater. If stored on isolated hard drives or on CDs tossed in desk drawers, it is probably not managed in a preferred manner. Again, the VNA provides a powerful way to fill in the gap.
The better way to archive
A VNA takes advantage of standards developed by the widely recognized IHE initiative. In addition to DICOM, these include XDS and XDSI, HL7 and others. Using this common data messaging, the VNA provides one comprehensive archive as the single point of information access for all the healthcare IT applications connected to it, even beyond the four walls of the enterprise that originally created the information.
Naturally, existing non-standard data must be transitioned to this formatting as part of the VNA migration process. The process can be handled efficiently and cost effectively by several VNA or third-party migration specialty vendors. Because the VNA contains diagnostic images, image enablement of an EMR and other systems becomes less challenging than with a siloed PACS archive. Providing this patient-centric storage
and information sharing will put a facility on the road to meaningful use.
Standardizing DICOM
As data is moved to the VNA, it stands ready to help. Through DICOM tag morphing, advanced systems can neutralize non-standard DICOM data, reconcile and manage patient identifiers from multiple sites and resolve inherent metadata discrepancies.
It is of note that some VNAs will also allow the altered DICOM header data to retain initial tagging so that it can still interact meaningfully with the system that created it or for full legal analysis at some future date.
Standardizing non-imaging DICOM objects, non-DICOM data
As noted, in addition to DICOM images, a VNA stores non-imaging DICOM data. This includes DICOM-structured reports, containing CAD and measurement data, and DICOM presentation states with user manipulations, such as shutters and overlays.
The VNA also stores and manages non-DICOM information from other specialty systems across the healthcare enterprise – including, for example, JPEG photos from dermatology and wound care, clinical PDF documents, waveforms from cardiology, video from sleep or gating studies, surgery, GI examinations, specialty formatted radiation oncology-treatment plans and more. These versatile storage capabilities make the VNA an appropriate repository for data from specialties as diverse as the lab and ophthalmology to speech pathology and dentistry.
Whether for DICOM or non-DICOM objects, once the object header is formatted with consistent patient identifiers as defined by the IHE, a simple search in the appropriate fields will gather the information necessary to create a comprehensive patient record. To facilitate this, the VNA includes a patient-centric content database that captures information from the object header such as patient name, patient ID, accession numbers and more. Information is recalled against the database using a standard storage query and retrieve protocol.
EMR integration
A key goal of the VNA is to provide access of stored data at the point of care, typically through an EMR system. While IT has long struggled to accomplish this, the VNA simplifies the task. A link to the standardized archive will bring up all these images, imaging-related data and information for each patient. Embed a lightweight DICOM viewer, and the result is an easy and elegant hospital-wide image-viewing solution that also can be used through any physician portal connected to the archive.
As a result, a site also has the ability to switch to any new standards-based PACS or other clinical system without costly data migrations or significant data reconciliation and cleansing. The VNA ends the era where a medical facility was tied to a particular vendor simply because its data was held captive in a proprietary format.
The VNA: Consolidated, cost-effective and efficient storage
The growing emphasis on the consolidation and sharing of medical information as a system of comprehensive patient records demands significant changes in most healthcare facilities’ IT infrastructure. The current patchwork of disparate IT systems with proprietary data storage formats creates major barriers to meaningful information organization and exchange, while elevating costs.
A VNA, such as TeraMedica’s Evercore, provides an elegant, cost-effective and efficient way to overcome these problems. By neutralizing data at the archival level, this advanced technology enables sites to leverage their existing IT applications, while facilitating cross-enterprise data sharing and streamlining the integration of medical images into the patient record.
About the Author
Greg Strowig is chief operating officer, TeraMedica. For more on TeraMedica: www.rsleads.com/307ht-201
