Vendor-Neutral Archive vs. PACS: Which Should a Hospital Choose?

A picture archiving and communication system (PACS) supports clinical workflows, while the vendor-neutral archive (VNA) supports long-term image management. For many hospitals, the key question is how to connect these layers efficiently.

If current trends continue, U.S. imaging utilization could be almost twice as high in 2055 as in 2023. The architecture decisions hospitals make now can determine whether their infrastructure can scale with increased demand. This page breaks down the VNA versus PACS decision to help you choose the right imaging architecture for your hospital.

What Each System Actually Does

PACS and VNA serve different functions within a hospital's imaging environment, so understanding what each one does can make the setup decision much simpler.

PACS: Clinical Workflow and Image Reading

PACS manages the worklist, hosts the diagnostic viewer and integrates with radiology information systems (RISs) and electronic medical record systems so that radiology workflow runs efficiently. It is optimized for speed of image retrieval and reading workflow at the department level.

PACS receives images from acquisition devices, routes them to the appropriate reading workstation and keeps them accessible for active clinical use. A PACS is usually DICOM-based, and some systems can package certain non-DICOM files into DICOM-compatible formats. Its architecture integrates storage, viewer and workflow in a single application-centric system, which is what makes it fast and clinically effective for reading.

VNA: Image Storage and Management

A VNA decouples the long-term storage layer from the clinical application layer. It stores imaging data in vendor-neutral formats, making it usable beyond any single PACS contract and accessible across departments and facilities.

A VNA gives IT a central way to manage medical images across multiple PACS, specialties and facilities. It handles long-term retention, data normalization across formats and access control at the enterprise level. 

Which Setup Fits Your Hospital?

The right setup depends on your hospital's size, number of facilities, existing vendor relationships and long-term budget.

PACS Only

Using PACS can be the right architecture for hospitals with contained imaging needs, whether they operate from one site or manage a limited set of connected workflows.

A standards-based PACS with cloud backup and disaster recovery could address many needs smaller hospitals may associate with a VNA. It can also support more complex workflow needs when routing, prefetch and reconciliation tools are in place.

For example, Munson Healthcare, a nine-site health system in northern Michigan, used prefetch technology to retrieve prior mammography studies from its PACS and make them available across facilities. The result was faster access to priors and less manual reconciliation of patient records.

PACS and VNA

Deploying PACS and VNA together is a common setup for multisite or multispecialty hospitals. PACS handles clinical reading and workflow, while VNA connects image access across the organization, retains historical data and makes future PACS migrations less disruptive.

Using both PACS and VNA is the right call when you have:

• Multiple departments each running their own PACS
• Growing imaging data from specialties beyond core radiology
• A PACS contract renewal where data portability or archive consolidation is a concern.

PACS/VNA integration depends on both systems supporting open standards. Not all VNA products can deliver true vendor neutrality, so confirm which standards the system supports before you commit.

Enterprise Archive Strategy

Enterprise archive strategies can be a significant investment for large health systems that need a formal governance layer for enterprise image consolidation across the organization. This strategy centralizes retention policies, supports compliance across sites and gives authorized clinicians access to imaging records from different locations. It can also create a consistent data foundation for AI tools without separate PACS integrations.

This approach makes sense when you have:

• A large multisite health system managing PACS across departments and other specialties
• Plans to use AI tools that need standardized access to imaging data
• Long-term data governance and regulatory compliance requirements
• The IT bandwidth to manage a complex multivendor architecture. 

Key Trade-Offs

Consider these key trade-offs when choosing between VNA and PACS.

Data Portability and Vendor Lock-In

A PACS that uses open DICOM standards and supports full study export on request offers portability without requiring a separate VNA layer. 

The VNA is most valuable when an organization needs to federate multiple PACS into a single neutral archive. 

Ask a vendor if you can export all studies in native DICOM format, without vendor assistance or additional fees.

Historical Image Migration

Migration can create operational risk during a PACS transition, which is one reason hospitals consider VNAs. A VNA can reduce migration complexity by maintaining a neutral archive through PACS changes. However, a PACS with strong migration tooling can achieve a similar outcome with less architectural complexity.

With a VNA, the archive is decoupled from the PACS, so a future PACS swap does not require migrating the entire historical record. 

Without a VNA, the migration depends entirely on the outgoing PACS vendor's cooperation and the tooling available for data extraction.

Disaster Recovery and Total Cost

Both systems support disaster recovery (DR), but at different scales and costs. A PACS with cloud backup handles DR for single-site operations, whereas a VNA-based architecture provides DR at enterprise scale across multiple systems.

A VNA adds licensing, integration work and ongoing management overhead. For smaller hospitals, a well-configured PACS with cloud backup could deliver similar protection at a lower cost. 

For larger systems managing multiple PACS, the VNA's TCO may be justified by reduced migration costs and simpler vendor management over the long term. 

Your PACS and VNA Procurement Checklist

Use this checklist to ask your vendor the right questions, whether you're considering PACS or VNA: 

• Calculate the total cost of ownership over a set number of years, including migration, integration and support.
• Determine whether all imaging data can be exported in native DICOM format without additional fees or vendor assistance.
• Confirm that the system meets your disaster recovery requirements and HIPAA compliance obligations.
• Check that it can scale to additional facilities or specialties without a full reimplementation.
• Verify that the system supports open standards such as DICOM, HL7, IHE XDS and FHIR ImagingStudy.
• Ask what a migration looks like and what tools the vendor provides to support it.

Talk to Candelis About Your Imaging Architecture

When your hospital needs a strong, scalable PACS, ImageGrid PACS by Candelis is built to deliver. 

ImageGrid PACS handles the full imaging workflow, from routing and storage to diagnostic viewing and disaster recovery through ASTRA Cloud, so your radiology team can focus on reading studies rather than managing infrastructure. 

Live Migration can handle the full transfer of your PACS and RIS data without interrupting your workflow. 

More than 3,700 healthcare facilities worldwide trust Candelis to archive and manage their studies. Several large facilities that switched to Candelis reduced service fees and operational costs by an average of 30%-50%. Contact our team to talk through your imaging architecture today.