A comparison of different VNA philosophies, their associated configurations and respective properties in deployment

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1 A comparison of different VNA philosophies, their associated configurations and respective properties in deployment Poster No.: C-2178 Congress: ECR 2013 Type: Authors: Keywords: DOI: Educational Exhibit P. R. Hart; Milwaukee, WI/US Patterns of Care, Image verification, Cost-effectiveness, Computer Applications-General, Teleradiology, RIS, PACS, Management, ehealth, Computer applications /ecr2013/C-2178 Any information contained in this pdf file is automatically generated from digital material submitted to EPOS by third parties in the form of scientific presentations. References to any names, marks, products, or services of third parties or hypertext links to thirdparty sites or information are provided solely as a convenience to you and do not in any way constitute or imply ECR's endorsement, sponsorship or recommendation of the third party, information, product or service. ECR is not responsible for the content of these pages and does not make any representations regarding the content or accuracy of material in this file. As per copyright regulations, any unauthorised use of the material or parts thereof as well as commercial reproduction or multiple distribution by any traditional or electronically based reproduction/publication method ist strictly prohibited. You agree to defend, indemnify, and hold ECR harmless from and against any and all claims, damages, costs, and expenses, including attorneys' fees, arising from or related to your use of these pages. Please note: Links to movies, ppt slideshows and any other multimedia files are not available in the pdf version of presentations. Page 1 of 10

2 Learning objectives This short paper seeks to: inform readers regarding the differences between a Vendor Neutral Archive (VNA) and a PACS alert readers with regard to some of the issues to consider when evaluating a VNA and comparing one VNA to another It does not purport to be a definitive statement as to the meaning of Vendor Neutral Archive nor is it an exhaustive or comprehensive assessment of the various ways of designing a VNA and implementing a VNA project. Background For as long as the IT infrastructure has been able to support it, there has been a growing acceptance in the professional medical community that a single, comprehensive, digital patient record will lead to better informed and safer diagnoses. If it were universally available at the point of need one could also expect more timely, effective and efficient treatments. Could this be a great idea whose time has come? Yes, but, as is often the case with paradigm-shifting realisations, making it happen has proved easier said than done. Even so, a small group of pioneers have developed solutions known as Vendor- Neutral Archives (VNA) which allow for a single-pane view of all clinical content. The VNA field is relatively young and definitions vary, but for this paper we shall take Vendor-Neutral Archive to mean a digital repository that is independent of the data source and serves multiple clinical applications both within and across medical specialties. The term itself, which is now in general usage, may yet be supplanted if a more meaningful one is coined to describe the same technology. To justify its name, a VNA must be general standards-based and accept, distribute and display information from numerous digital systems, modalities and file sources from any manufacturer, IT solution or originating department. The defining characteristic of a VNA is that its design philosophy and functionality revolve around the patient. This is in stark contrast to most other healthcare file systems which are department-based and tied to the clinical applications that created them, like PACS for medical imaging. Imaging findings OR Procedure details Page 2 of 10

3 The key features of a VNA compared to PACS may be summarised, as: VNA Patient-centred / trans-departmental Multiple standards-based - DICOM, HL7, non-dicom etc Seamless interface with RIS, HIS and EMR Accept, distribute, display images and medical information from numerous disparate digital systems anywhere Free information / support data-sharing (XDS) Aggregate and consolidate enterprisewide clinical content Integrate the entire medical enterprise to facilitate EMR PACS (+ other service-based systems) Service-centred department-based DICOM and proprietary PACS-based formats DICOM/HL7 incompatibility issues Accept, distribute, display medical images only from and within the (usually proprietary) PACS Hold information / inhibit data sharing (limited XDS) Separate and fragment partial information Enable the single department but may hamper EMR Transfer data ownership to the facility Preserve data ownership with the department and/or PACS supplier Multiple distributed points of universal access Universal Viewer - usually web-based / "zero" footprint Accelerate and facilitate impending data migration Eliminate further data migrations Enable replacement of PACS supplier Heal and harmonise diverse patient data across specialties Sophisticated and customized rules-driven intelligence eg clinical information life-cycle management (ILM) Limited department-centred points of access Specialty-specific viewer - usually systemhardware-based Retard and hamper impending data migration Perpetuate further data migrations Obstruct changes of PACS supplier Limited or absent data healing and harmonisation Limited or absent intelligence Traditional PACS has, in essence, been developed over decades to do a different and much easier job than a VNA. Aware of the considerable limitations of PACS and in response to the advent of VNA, some PACS companies have produced Enterprise-Wide Page 3 of 10

4 PACS, variously dubbed super-pacs or PACS 2. These enhanced PACS solutions can receive information from non-medical-imaging specialties as well as Non-DICOM files. Even so, viewing and storing the images are restricted to the PACS and its archive which continues to tie the user to a single PACS supplier and interface. If VNA seems, then, to be the rational response to the greater medical facility's growing need for comprehensive and immediate patient information at the point-of-care, why are there so few VNA's out there? The simple answers are that the developmental challenges of a VNA are massively greater than those of PACS and in many respects the starting point of a mature PACS can be a disadvantage. It is indeed technically and practically difficult and corporately awkward to jettison the relatively limited thinking and associated expertise of decades as well as abandon substantial historic investment. This reality is reflected in the number of PACS companies, which runs to hundreds worldwide, compared to true VNA companies which are still only a handful. The predicament of the PACS providers is aggravated when it is realised that much - if not all - of the job of the PACS can be done by a decent VNA but only a small part of the job of the VNA can be done by PACS Figures 1-to-2 (below) illustrate a simplified evolution of the VNA from its historic precursor, PACS. Figure 1 is a schematic of some typical variants of traditional PACS, all of which manifest department-centred vertical architecture. Figure 2 shows how the VNA layer fits logically in the space between the clinical and storage layers in new and existing installations to integrate all the specialties, to the HIS and RIS and add intelligence to the handling and archiving of clinical content of the patient and around the patient to yield a more comprehensive EMR functionality. Figures 3/4 (below) shows a schematic of the TeraMedica Evercore product configuration alongside that of another true VNA to illustrate differences that might be significant in meeting client requirements. While both solutions are truly patient-centred; the chief structural difference is that of the single instance patient record embedded in the TeraMedica EverCore architecture compared to the multiple instance patient record in another example of VNA. Given that the achievement of true universality, flexibility and robustness within the VNA are technologically challenging, a number of companies have in response adopted what appears to be a reduced design and development brief for their VNA. For example, ascribing a client table to multiple nodes within the organisational matrix - which is an expedient design practice that can be justified for a fixed organisation size and structure - can result in a profusion of tables that becomes problematic or even unmanageable over time, especially as clinical images and objects proliferate and organisations grow and change. While the proposition of a simplified structure may sound persuasive at the outset the latent complications of multiple-node design may require frequent provider Page 4 of 10

5 intervention to migrate and delete tables or find and reconnect dissociated structures. Mindful of such eventualities TeraMedica has not watered-down the task but instead embraced a total design philosophy to produce an enduring enterprise VNA with only a single-instance patient entry. VNA project implementation under this philosophy not only minimises external support interventions over time but also massively reduces the dependency burden on the local database administrator. All parties gain. Beyond the philosophical and logical aspects inherent in the configurations of competing VNA's, differences with regard to user requirements can also be found in how alternative suppliers manage clinical content; an important and signal example is in the handling of Non-DICOM objects. While the storing of DICOM Part 10 files is an established procedure well known by PACS and VNA companies alike, the crucial incorporation of Non-DICOM objects can be handled in a variety of ways that can greatly enable or significantly limit the utility of a VNA. TeraMedica, for example, believe that objects should be moved, stored and retrievable in their native format; a DICOM-object should be stored appropriately as a DICOM-object and a Non-DICOM object in its native Non-DICOM format; a PDF for example - by its nature a document that is universally readable - should be stored and retrieved as a PDF. Perhaps surprisingly, however, it is nonetheless the case that some VNA providers encapsulate and store Non-DICOM objects in either proprietary encrypted formats such as.tar and.asf while others "wrap" the Non-DICOM object in a.dcm header and then store it in a DICOM format as a newly generated DICOM object. Both of these methods restrict any secondary reading of the object to the VNA when documents in the widely adopted.pdf format, for example, should be readable both within and outside of the VNA. Such an approach would seem to defeat the philosophical and practical aims of VNA which are to provide, as stated at the start of this paper, universal availability and multiple points of access. Images for this section: Page 5 of 10

6 Fig. 1: Examples of Typical Departmental PACS NB Vertical silos of service-related files Page 6 of 10

7 Fig. 2: Illustration of logical and functional location of VNA layer in a new or existing PACS/EMR structure Page 7 of 10

8 Fig. 3: TeraMedica Evercore VNA Configuration Manifesting single-instance storage of patient-centred clinical content in aggregated and consolidated data silos Page 8 of 10

9 Fig. 4: Another VNA Configuration Manifesting multiple-instance storage of patientcentred clinical content in institution-defined discrete vertical data silos Page 9 of 10

10 Conclusion Through a wholesale re-modelling of radiology based on digital technology, PACS has significantly contributed to increased productivity and improved clinical effectiveness of medical imaging while demonstrating the benefits of integration. Paradoxically, however, in successfully realising its potential PACS has also exposed its own limitations. With the radiological model well proven, the greater clinical community is now becoming aware that a single-specialty or department-based solution is not sufficiently intelligent, versatile or integrated to address ever increasing demands of the patient within the whole medical enterprise. These kinds of inadequacy are especially inconvenient and apparent as the EMR now seeks to embrace multiple specialties in order to provide integrated and holistic clinical information. It is not sufficient for existing PACS simply to add a few integration features to operate as a VNA and only a true VNA can deliver all the higher level supra-departmental and trans-departmental functions. Moreover, even the small number of true VNA's currently offered are based on different philosophies which are implemented in different configurations and have different clinical benefits. As the paradigm shifts end-users and institutions need to be aware of the differences between enhanced PACS and VNA, as well as between different VNA's, to ensure they choose the right solution to meet their requirements. References All references used within this paper are based on private and corporate communications. Personal Information Declaration of Interest The author is an employee of TeraMedica, Inc Innovation Drive Milwaukee WI USA TeraMedica, Inc. is a manufacturer of vendor neutral archives Page 10 of 10