Ocular imaging and instrument-based assessments of visual function (e.g., optical coherence tomography or automated perimetry) are essential elements of evidence-based clinical eye care and are increasingly important as objective clinical outcome measures in patient-based research. These medical devices are often deployed as an integrated component in a medical informatics environment designed to communicate data and images across that environment with other integrated devices, such as electronic health records, storage and retrieval systems, and analytical platforms. The interoperability standards for these medical devices are defined by voluntary consensus and authored by the Digital Imaging and Communications in Medicine committee.

BACKGROUND

First formed in 1983 by the American College of Radiology and the National Electrical Manufacturers Association, this joint committee sought to address imaging and communication standards for the emerging field of digital imaging, as well as the ability to store, retrieve, and display digital images and their associated information across hospital information systems. The third iteration of this committee’s standards were issued in 1993 as Digital Imaging in Communication and Medicine (DICOM). These standards defined network communication protocols, off-line data storage and exchange, semantical protocols for data exchange, and levels of conformance with DICOM standards. The DICOM standards are designed as evolving standards, open for comment, revision, and enhancement, and are updated by the committee periodically.

LIMITATIONS

Because DICOM standards are voluntary and interpretations can vary, there are limitations to the functionality that can be guaranteed through application of these standards. Nevertheless, these voluntary standards have been effectively implemented in radiology, cardiology, and other medical specialties, enabling wide integration and interoperability across the health care system. Unfortunately, there is much less consistency in ophthalmic imaging.

The DICOM standards specify:

Network communication protocols for devices claiming conformance. Syntax and semantics for information that can be exchanged using DICOM protocols. Standards for communication and directory structure information relating to media storage services that facilitate image storage and data retrieval.

The DICOM standards do not specify:

Implementation details for features on a device claiming compatibility The overall set of features and functions to be expected from a system implemented by integrating a group of devices claiming DICOM compatibility Validation procedures to assess adherence to the standards.

In practice, manufacturers of ophthalmic imaging devices may or may not conform to the standards. Moreover, even when manufacturers claim consistency with DICOM standards, they may not fully implement the standards, or achieve the principles of integration and interoperability that is required to make full use of the available data and images. When manufacturers fail to support the principles and technical specifications of DICOM standards, there are detrimental effects on patient care and barriers to the use of ocular imaging data in clinical research that serves the public interest. It is also important to recognize that the DICOM standards represent a conceptual framework for these procedures, because new innovations will modify the details of their implementation.

CALL FOR ACTION

Optometry and Vision Science fully supports recent calls from the National Eye Institute and other stakeholders including academic societies, scientific journals, instrument manufacturers, and health care IT specialists seeking greater consistency with imaging standards to enhance the integration of imaging devices in medical informatics systems. Wider adoption of these standards would not only improve patient care, but would also enhance the ability of clinical investigators to use image data in biomedical research including objective outcome measures in human clinical trials. Failure to implement DICOM standards creates real barriers to innovations in patient care, evolution of evidence-based care standards, and research discoveries that can advance our understanding of human eye diseases, their treatment, and future therapies. We further encourage individual support through public comments and participation in the upcoming joint workshop: Promoting the Adoption of Ocular Imaging Standards.https://www.nei.nih.gov/about/goals-and-accomplishments/nei-research-initiatives/data-science-and-health-informatics/nei-fda-onc-joint-workshop-promoting-adoption-ocular-imaging-standards.

Michael D. Twa, OD, PhD, FAAO
Editor in Chief University of Houston College of Optometry Houston, TX
Chris A. Johnson, PhD, FAAO
The Ohio State University Columbus, OH