Digital Retinal Imaging Eye Test

Digital retinal imaging is fast becoming an additional part of having an annual wellness eye examination. Next time you check in to your optometrist's office for your routine vision exam, chances are you will be given a form to consent to undergo an additional test that many eye doctors are now performing as an enhancement to their comprehensive eye examination.

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About Digital Retinal Imaging

With the advent of digital photography, the eye care industry now produces digital retinal cameras that produce an amazing view of the inside of the eye. Digital retinal imaging is the act of taking a digital photograph of the inside of the eye including the retina, optic nerve, macula, and blood vessels. This image is used to screen for eye diseases and can be used to compare to images taken in future examinations.

If a condition or disease is found, the doctor will repeat the test with a higher resolution and other imaging tests, such as fundus photography, ocular coherence tomography (OCT), and B-scan ultrasonography. Routine digital retinal imaging is usually performed at a lower resolution for screening purposes and serves as a baseline test.

Cost

While vision care plans will cover a dilated retinal examination of the eye, they will not cover retinal imaging. However, the retinal imaging can provide the doctor with additional information than just dilation alone. Most eye doctors charge a nominal fee that ranges from $15-$50.

An Inside View

There are differences between a routine vision screening exam and a comprehensive medical eye examination. However, most eye examinations include a part of the examination where dilating drops are instilled into the eye. This causes the pupil to enlarge so the doctor can look into your eye and is the standard of care. Sometimes, due to small pupils or patient cooperation, it can be difficult for the optometrist or ophthalmologist to visualize everything they need to see.

Digital retinal imaging may provide a different view of the retina that sometimes gives the doctor clues about certain eye conditions. Some of these subtle changes can be better seen by digital retinal imaging.

What About Eye Dilation?

Does this test mean I don't have to have my eyes dilated, you may ask. No. Physically looking into the eye is still invaluable. However, using digital retinal imaging provides different types of information. Combining both allows the eye doctor to make a better health assessment.

Equipment Used

There are basically three different types of machines that can perform digital retinal imaging. Each one provides a unique view of the inside of the eye and each one uses a different technique to obtain the images. There are advantages and disadvantages to all three methods.

• Fundus Cameras - Digital fundus cameras are available by several manufacturers. They produce a 30-50 degree view of the retina.
  Although the field of view is only 45 degrees, fundus cameras give the highest resolution images available.
• Optos UWF (Ultra-wide field imaging) - Optos uses a special patented technique that allows up to a 200-degree image of the retina to be seen without using any special dilating eye drops. Optos UWF instruments are very popular among eye doctors. Centervue's Eidon - Centervue's Eidon uses a true color confocal scanner. It can take a 60-degree image in a single exposure but can provide a much larger view with additional functionality, combining up to seven different images for a 110-degree view.
  The Optos provides a wider field of view, but the Eidon instrument provides better resolution and color.

A Word From Verywell

While digital retinal imaging can be a helpful add-on to a routine dilated eye exam, it does not replace it. If you have any existing medical conditions, such as diabetes, hypertension, an auto-immune disorder or a family history of disease that can cause vision loss, a standard medical eye examination should always be performed and not replaced by a routine screening.