Diabetic Eye Disorders


Diabetes can affect sight

If you have diabetes melitus, your body does not use and store sugar properly.  High blood-sugar levels can damage blood vessels in the retina, the nerve layer at the back of the eye that senses light and helps to send images to the brain.  The damage in retinal vessels to referred to as diabetic retinopathy.

Types of diabetic retinopathy




Unfortunately, the new, abnormal blood vessels do not resupply the retina with normal blood flow.  The new vessels are often accompanied by scar tissue that may cause wrinkling or detachment of the retina.


Proliferative diabetic retinopathy causes visual loss in the following ways:
Vitreous hemorrhage:  The fragile new vessels may bleed into the vitreous, a clear jelly-like substance that fills the center of the eyes.  If the vitreous hemorrhage is small, a person might see only a few new dark floaters.  A very large hemorrhage might block out all vision.

It may take days, months or even years to resorb the blood, depending on the amount of blood present.  If the eye does not clear the vitreous blood adequately within a reasonable time, vitrectomy surgery may be recommended.

Vitreous hemorrhage alone does not cause permanent vision loss.  When the blood clears, visual acuity may return from its former level unless the macula is damaged.


Neovascular glaucoma:  Occasionally, extensive retinal vessel closure will cause new, abnormal blood vessels to grow on the iris (colored part of the eye) and block the normal flow of fluid out of the eye.  Pressure in the eye builds up, resulting in neovascular glaucoma, a severe eye disease that causes damage to the optic nerve.

How is diabetic retinopathy diagnosed?

A medical eye examination is the only way to find changes inside your eye.  An ophthalmologist can often diagnose and treat serious retinopathy before you are aware of any vision problems.  The ophthalmologist dilates your pupil and looks inside of the eye with an ophthalmoscope.

If your ophthalmologist finds diabetic retinopathy, he or she may order color photographs of the retina or a special test called fluorescein angiography to find out if you need treatment.  In this test a dye is injected into your arm and photos of your eye are taken to detect where fluid is leaking.

How is diabetic retinopathy treated?


Laser surgery:  Laser surgery is often recommended for people with macular edema.  PDR and neovascular glaucoma.

For macular edema, the laser is focused on the damaged retina near the macula to decrease the fluid leakage.  The main loss of vision.  It is uncommon for people who have blurred vision from macular edema to recover normal vision, although some may experience partial improvement.

A few people may see the laser spots near the center of their vision following treatment.  The spots usually fade with time, but may not disappear.

For PDR, the laser is focused on all parts of the retina except the macula.  This panretinal photocoagulation treatment causes abnormal new vessels to shrink and often prevents them from growing in the future.  It also decreases the change that vitreous bleeding or retinal distortion will occur.


Vitrectomy:  In advanced PDR, the ophthalmologist may recommend a vitrectomy.  During this microsurgical procedure, which is performed in the operating room, the blood-filled vitreous is removed and replaced with a clear solution.  The ophthalmologist may wait for several months or up to a year to see if the blood clears on its own before performing a vitrectomy.


Vision loss is largely preventable

if you have diabetes, it is important to know that today, with improved methods of diagnosis and treatment, only a small percentage of people who develop retinopathy have serious vision problems.  Early detection of diabetic retinopathy is the best protection against loss of vision.


When to schedule and examination

People with diabetes should schedule examinations at least once a year.  More frequent medical eye examinations may be necessary after the diagnosis of diabetic retinopathy.
Pregnant women with diabetes should schedule and appointment in the first trimester because retinopathy can progress quickly during pregnancy.  If you need to be examined for glasses, it is important that your blood sugar be in consistent control for several days when you see your ophthalmologist.  Glasses that work well when the blood sugar is stable.

  • Affect only one eye
  • Last more than a few days
  • Are not associated with a change in blood sugar


  • Within five years of the diagnosis if you are 30 years old or younger
  • Within a few months of the diagnosis if you are older than 30 years

Adapted from Wikipedia http://en.wikipedia.org/wiki/Diabetic_retinopathy