Tests and diagnosis

By Mayo Clinic Staff

Diabetic retinopathy is best diagnosed with a dilated eye exam. For this exam, your eye doctor will place drops in your eyes that make your pupils open widely. This allows your doctor to get a better view inside your eye. The drops may cause your close vision to be blurry until they wear off several hours later.

During the exam, your eye doctor will look for:

  • Presence or absence of a cataract
  • Abnormal blood vessels
  • Swelling, blood or fatty deposits in the retina
  • Growth of new blood vessels and scar tissue
  • Bleeding in the clear, jelly-like substance that fills the center of the eye (vitreous)
  • Retinal detachment
  • Abnormalities in your optic nerve

In addition, your eye doctor may:

  • Test your vision
  • Measure your eye pressure to test for glaucoma.

Fluorescein angiography

As part of the eye exam, your doctor may do a retinal photography test called fluorescein angiography. First, your doctor will dilate your pupils and take pictures of the inside of your eyes. Then your doctor will inject a special dye into your arm. More pictures will be taken as the dye circulates through your eyes. Your doctor can use the images to pinpoint blood vessels that are closed, broken down or leaking fluid.

Optical coherence tomography

Your eye doctor may request an optical coherence tomography (OCT) exam. This imaging test provides cross-sectional images of the retina that show the thickness of the retina, which will help determine whether fluid has leaked into retinal tissue. Later, OCT exams can be used to monitor how treatment is working.

Mar. 27, 2012

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