Moving to modern ophthalmic image management

What you need to know before taking the plunge into digital image management systems.

By Michael V. Boland, MD, PhD

The typical ophthalmic practice is an increasingly electronic place. It is not always the case that a practice utilizes a single system for all of its data management needs, however. A fully electronic ophthalmic practice may need different systems to accommodate practice management (patient registration and scheduling), billing, medical records and image management. The American Academy of Ophthalmology’s recent survey of member practices revealed the vast majority were already using electronic systems for practice management.

It is also true that the rate of adoption of EHR has increased significantly since that survey and a majority of practices are now capturing clinical information electronically.¹ These numbers for EHR adoption in ophthalmology are comparable to other medical specialties. One area in which eye care differs from most of medicine, however, is the need to manage the images and data from a wide variety of in-office testing devices. Systems to manage these images have evolved slower than EHR, but are clearly an important consideration in an otherwise electronic office.

Data from multiple testing devices

The eye affords us the unusual opportunity to directly assess both normal and abnormal structures and function for most of the organ system we care for. Because of this, we now have a long list of devices devoted to collecting quantitative information about the eye. This includes imaging of the anterior and posterior segments with laser-based devices such as OCT, photography and ultrasound.

We can also measure all visible structures of the eye to assess the shape of the cornea (topography), determine overall refractive error and plan for lens implantation (biometry). We regularly assess the functional state of the eye with automated perimetry, electroretinography and visual evoked potentials, all of which produce quantitative (digital) information.

Once these data are generated, however, we face the issue of how to store and transmit them to the physician who needs them to make diagnostic or management decisions. Here, we review our current options, and glimpse at an improved approach to image management.

MANAGEMENT OF ANCILLARY TESTING DATA

In the beginning was paper

Because not all offices manage their testing data electronically, any ophthalmic testing device purchased today includes the capability to output standard reports on paper. Manufacturers design the reports their devices generate to be produced on paper (Figure 1). And regardless of whether we document patient data electronically, transmitting that information to another physician usually requires sending paper via mail or fax.

Figure 1: Examples of device reports designed for printing on paper.

The clear downside to using paper-based reports is that we are not taking advantage of the digital nature of the data the device captures. Once the testing device processes those data and then prints the report on paper, we cannot reprocess the data or view it in any way other than the original report. It is also clear transmitting these reports that paper is not always effective. (Have you seen a faxed copy of a color OCT report?)

Going ‘picture-based’

The next step for many practices once they decide to move away from paper and film is to convert to a digital image management system. These systems allow physicians to review images and reports on a computer, and can improve workflow that relies on an electronic medical record. They typically import images from each testing device, either via a manual process or by capturing the output that would have gone to the printer. Used this way, these systems are really just capturing images of the reports we were used to on paper. The advantage is really that they help get rid of the need to print, route and store paper reports (Figure 2, page 49).

Figure 2: Images of reports that would otherwise be printed but as they appear in a typical image management system.

One downside to “picture-based” data storage and review is that the link to a real person is not always perfect because the image management system sometimes imperfectly extracts patient demographic information from the device or it was entered incorrectly in the first place (eg, misspelled name, transposed numbers on a birthdate). Another disadvantage is that we are really just using the computer to view a static report designed for paper. Finally, these systems store no real data, so the physician has no opportunity to reanalyze the images later either to determine change or to take advantage of new analytic methods.

The goal is an integrated system

Given the disadvantages of paper and picture-only digital systems, what should we strive for as a means of managing our images in ophthalmology? Ideally, the management of images and test results should integrate with the other electronic systems in the practice, particularly the practice management system and electronic health record. Whenever possible, you should also capture and store the actual data from the test device. By linking patient registration and image management systems, it is possible to ensure that the test results are linked to “real” patients, alleviating the misidentification problem present in most current image management products.

The storage of the underlying data will also allow for the reanalysis and interactive analysis of the clinician’s results (Figure 3). Rather than looking at static reports, for example, you can update and modify analyses during the patient encounter without the need to go back to the device itself. Storage of actual data will also allow us to transmit patient records to colleagues with no loss in fidelity as we now see with paper.

Figure 3: Example of an interactive review system for visual field data, allowing the physician to select tests to be included in the analysis and perform analyses not available on paper, such as dual baselines, viewing tests as a movie, and others.

DICOM COMES TO OPHTHALMOLOGY

Solution from another specialty

How do we move toward more robust digital systems to manage ophthalmic images? The best answer comes from radiology, which experienced the problems of large-scale digital image management decades before most other specialties. Radiology developed the Digital Imaging and Communications in Medicine (DICOM) standard, which specifies how images should be stored, transmitted and linked to patient information.²

DICOM allowed health-care systems and hospitals to select imaging devices from different vendors and tie them together with picture archiving and communication systems (PACS). These PACS rely on the DICOM standard to allow radiologists to review images from any of the connected devices (MRI, CT, plain film, ultrasound, etc.).

Fortunately for ophthalmology, DICOM is an open standard that extends to the needs of our specialty. The AAO noted this in the late 1990s, and since then has sponsored a working group to add standards to DICOM to accommodate the kinds of testing we perform in our offices.

The ophthalmology-specific DICOM standards now available include ophthalmic photography, ophthalmic tomography (including OCT), refractive measurements, axial length measurements, static perimetry, thickness mapping (including macular imaging) and corneal topography. These additions to DICOM, along with pre-existing standards for modalities like ultrasound, now cover almost all of the testing we perform and can serve as the basis for a DICOM solution in ophthalmology.³

Vendors are buying in

Once these DICOM standards are available, vendors must implement them in their products before we can take advantage of them. Fortunately, this is now taking place, with vendors reporting implementation of DICOM in both imaging devices and image-management systems. To help members identify vendors doing their part in terms of DICOM implementation, the AAO has begun to survey them. The latest results are available at tinyurl.com/AAO-guidelines.

What you should do

Many ophthalmology practices are not comfortable with the details of electronic systems. Fortunately, DICOM has features to make this easier, at least for the image-management component. Whenever you are considering the purchase of a new imaging or testing device, ask the vendor for its DICOM conformance statement.

This is a document specified in the DICOM standard in which the vendor must explicitly declare which aspects of DICOM are implemented in the product in question. Using this information, our practice has been able to integrate devices from multiple vendors.

The previously mentioned AAO survey summarizes similar information about device-DICOM compatibility. If your vendor representative either does not know what a DICOM conformance statement is or takes more than about five minutes to send you a link to it online, you should be skeptical of the vendor’s commitment to the standard.

How to use a DICOM conformance statement

Once you have a vendor’s DICOM conformance statement in hand, the next step is to determine which pieces of the large, complex DICOM standard it really implements. The conformance statement should explicitly list which DICOM standards have been implemented — look for the ophthalmology-specific standards mentioned previously. The AAO survey of device-DICOM compatibility, which asks explicitly about the differing levels of DICOM implementation, also provides this information to you.

This is important, as you will, all other things being equal, prefer the product that has implemented the ophthalmology-specific DICOM standards. This is because DICOM includes a method of attaching patient demographics to a picture and then transmitting that for storage in a PACS. While this approach is technically DICOM compliant, it does not allow us to achieve all that we hope in terms of data storage and more interactive analysis of those data.

As is frequently the case in periods of rapid technological change, we are presented both with an opportunity to move toward more robust management of testing and image data and the challenge of making complex decisions about how to proceed that will impact the way our practices care for patients. OM

REFERENCES

About the Author
	Michael V. Boland, MD, PhD, is Director of Information Technology, Wilmer Eye Institute, Johns Hopkins University and Vice Chairman of the Medical Information Technology Committee of the American Academy of Ophthalmology. Disclosure: Dr. Boland has received speaking fees from Carl Zeiss Meditec.