Screening for diabetic macular edema: How often?

Regular screening for diabetic macular edema is key to preventing vision loss.

Diabetic macular edema is a complication of diabetes that can cause vision loss. It often occurs with no symptoms. If you have diabetes, it's important to schedule regular eye exams to screen for this complication and preserve your vision.

A comprehensive eye exam can detect swelling (edema) in the macula at the back of your eye. The macula is essential to your central vision and allows you to see in fine detail.

If you have type 2 diabetes, your doctor may recommend that you have a comprehensive eye exam immediately after diagnosis. If you have type 1 diabetes, it's recommended that you have an eye exam within three to five years of diagnosis.

In either case, you'll need to schedule ongoing, yearly eye exams after your initial eye exam to look for signs of damage from diabetes. Simply having your eye prescription tested isn't enough. Your doctor might recommend more-frequent exams if there's already some damage in your retina (retinopathy). If you're pregnant, your doctor may also recommend an eye exam during your first trimester, with follow-up exams throughout pregnancy and for one year after delivery. That's because blood sugar levels can spike during pregnancy and affect the eyes. For most women, this is temporary and goes away soon after delivery.

What to expect during your eye exam

A comprehensive eye exam is done by a doctor who specializes in treating disorders of the eyes (ophthalmologist or optometrist). This exam includes several tests:

  • Vision check. You'll read an eye chart. You'll also stare at a central target and then indicate in some fashion — such as by pushing a button or saying something to your doctor — when you see an object at the sides of your vision (peripheral vision).
  • Retinal exam. A dilated eye exam can help your eye doctor get a good look at your retina. Your doctor will place special drops in your eyes to open up (dilate) your pupils and make them larger. This will allow him or her to fully examine the backs of your eyes, to help detect diabetic macular edema and other eye problems. Your doctor may also offer retinal screening photography without dilation.
  • Tonometry. Your doctor will measure the pressure in your eyes. High pressure can cause you to lose vision from damage to the optic nerve (glaucoma).

Don't wait for your annual eye exam if you experience blurred vision, feel pressure in your eyes, or have trouble seeing at any distance. Contact your doctor immediately. Early detection and treatment of diabetic macular edema can help prevent vision loss.

Jan. 23, 2015 See more In-depth