Ruth E. Dayhoff, MD, Department of Veterans Affairs; Julian Werfel; Daniel Carozza, MD; Peter M. Kuzmak; Stuart A. Frank

Patient images from remotely located medical facilities can be delivered seamlessly to improve patient care

The US Department of Veterans Affairs (VA) has the largest integrated healthcare network in the United States. It operates a complete multimedia patient record system that is deployed at all of its 158 medical centers and many of its 600 outpatient clinics. Images are acquired for the system from a variety of devices and subsystems. VA patients are often treated at more than one VA facility and have images and patient records located in more than one hospital system. Electronic access to the patient’s medical images from other facilities is necessary to provide the best and most comprehensive patient care.

The VA uses a comprehensive healthcare system called VistA at all of its medical centers. VistA includes a hospital information system (HIS), a Computerized Patient Record System (CPRS), and the multi-specialty VistA Imaging System (VI). When combined, these systems provide a fully integrated multimedia patient record.[1] Over 800,000,000 images are available online, along with the relevant reports, notes, and consults. Medical images originate from a wide variety of specialties including radiology, cardiology, gastroenterology, pulmonary, dental, eye care, dermatology, and nursing. Scanned documents, electrocardiogram waveforms, and electronically produced reports are also available. Images may be captured using a standard DICOM interface, a clinical capture workstation, or an interface to commercial systems.[2] Most VA imaging systems are physically located at the medical facilities to reduce bandwidth requirements. But it is important that clinicians have access to images stored at any other VA medical facility where a patient has been treated.

A federated system approach is well-suited to address these requirements. A typical federated system consists of a set of separate, autonomous but integrated information systems that offer a uniform way to access data stored by various data sources.[2] The autonomy of the individual records and systems is maintained, and ensures HIPAA and security compliance. In order to use a federated approach, a number of changes were required to the existing systems:

• Image index terminology was standardized across all sites in the VA.[3] The VA selected five major index axes: origin of the image, class of the image, type of image/document, specialty/subspecialty, and procedure/event. Within each axis, standardized terms were defined. These terms are applied to each image or study that is captured. This allows easy retrieval of pertinent patient images stored at facilities across the country based on these standard index terms.

• A master patient index system is essential in identifying patients within the healthcare network, and allowing access to their images. Role-based access to images is required to view information from other facilities. This is based on the relationship between the clinician and the patient. Clinicians are prevented from viewing patient information for patients for whom they are not care providers at their home facility. In addition, clinicians are warned if a patient’s record is sensitive at any site. They may then choose whether to view the record. Such accesses are specifically audited. Another key capability is the ability to identify medical centers where each patient has been treated.

• A standard interface is used for the submission of requests and the receipt of images in required formats. Each member of the federated system was required to support this interface. Systems can be similar or disparate, as long as they meet the interface requirements and are capable of responding efficiently to queries. This will allow the VA to operate with outside systems when necessary.

• Finally, user interface software was modified to allow user selection of remote images and associated reports for viewing and comparing on the clinical workstation. A later addition included the capability of caching images in the background while the user completes other tasks.

• Privacy and Security requirements of the Federal Government must be implemented. These requirements go beyond those of the private sector, such as HIPAA, and may preclude the use of standards such as XDS.

These modifications were implemented, and the resulting capabilities are called “Remote Image Views.”

Remote Image Views capabilities have provided important benefits to both patients and clinicians. A survey of system users at various hospitals reported the following qualitative results and improvements in patient care workflow based on the Remote Image Views capability:

• Huge time savings via immediate access to images from any other point on the VA healthcare network, without contacting the other facility
• Avoidance of unnecessary redundant testing, which is often otherwise done when images and reports are missing
• Patient wait times are reduced because all information is immediately available, and medical decisions can be made rapidly
• Continuity of care is tremendously improved, because the complete electronic healthcare record is available, no matter where the patient is within the VA healthcare network
• Decisions are better informed, because Remote Image Views allow clinicians to review images and report directly, providing a better understanding of the patient’s care in the past and of the treatment the patient has been receiving
• No need to make hard copy of images or films to send with the patient for a referral visit. Thus, films are not delayed or missing when the patient is referred to another VAMC
• Images and reports from outside the VA network are imported into VistA Imaging and are available throughout VA
• Disaster response is improved, because the images of displaced patients can be available at other VA facilities where the patients have been relocated, without physically moving the image storage devices.

Usage monitoring of Remote Image Views for eye care screening demonstrated an increase from 900 studies/month to 6,900 studies/month over an 18 month period. Other specialties are using Remote Image Views for routine patient care, as well as telemedicine.

The VA healthcare imaging network is achieving important benefits for patients and clinicians through its federated system architecture. Images and scanned documents are all online and available. Clinicians may view their patients’ medical images and reports, regardless of which facility provided care. Users can select studies from a consolidated list for the display and comparison. This has been accomplished through a series of modifications to VistA Imaging that have had a very powerful effect. Essential patient information is instantly available at any of the hundreds of points within the nationwide healthcare network where a patient may receive care. Clinicians interact with the user interface they are accustomed to. Most images are available within seconds.

Essential patient information is instantly available at any of the dozens of points within the nationwide healthcare network where the patient may receive care. This capability helps the VA control its healthcare delivery costs, while treating a larger patient base with increasingly complex pathologies. Advanced informatics practices, such as Remote Image Views, can be expanded to serve additional patients and serve a wider population.

1. Dayhoff RE, Kuzmak PM, Meldrum K. Providing an Online Multimedia Patient Record. HIMSS 2001. Available at: http://www.himss.org/content/files/proceedings/2001/sessions/ses038.pdf.

2. Henderson ML, Dayhoff RE, Frank S, Kirin G. Success of a prioritized mapping algorithm for cross-facility regularization of image indexing. Medinfo. 2004.

3. Busse S, et al. Federated Information Systems: Concepts, Terminologies, and Architecture. Forschungsberichte des Fachbereichs Informatik Bericht Nr. 99-9. Available at: http://lsirwww.epfl.ch/courses/cis/2001ss/exam/Part%202%20DB%20integration.pdf.