What is Diabetic Retinopathy?

Introduction

• Diabetic retinal disease (diabetic retinopathy) is the most common cause of visual impairment and blindness among Americans between the ages of 25 and 74.
• Up to 90% of diabetic blindness can be prevented with regular dilated eye exams, which facilitate early detection and timely treatment.
• Our mission is to reach out to people with diabetes who are unaware of the importance of a simple eye examination, which could make the difference between seeing and not seeing.
• Vision loss is preventable but remains a major unresolved challenge because of delays in diagnosis.

Scope of The Problem

• There is an epidemic of diabetes in the United States.
• According to the Centers for Disease Control ¹:
  1. There has been a 15% increase in type 2 diabetes since 2005.
  2. 24 million Americans (8% of the population) now have diabetes.
  3. 57 million Americans are pre-diabetic.
• 4.4 million Americans have diabetic retinopathy.
• 1 million Americans have a vision-threatening disease.
• 40% of adults over the age of 40 who have diabetes also have diabetic retinopathy.

Clinical Summary of Diabetic Retinopathy

• The retina is the delicate membrane which lines the interior of the back of the eye—much like film in a camera. It contains highly specialized nerves which sense light, and small blood vessels which provide the nerves with oxygen and nutrients.
• The macula is the small spot located in the center of the retina which is responsible for high definition vision. For instance, we use the macula to read a magazine, drive a car, or watch TV.
• Diabetic retinopathy is the term used to describe the damage that elevated blood sugar levels produce in the small blood vessels located within the retina.
• Diabetic retinopathy is classified in two broad categories:
  1. Background or non-proliferative retinopathy
  2. Proliferative retinopathy

• Macular swelling (edema), which is caused by leaking microaneurisms, is the most common cause of visual loss among adult onset diabetics.

• Proliferative diabetic retinopathy is a more advanced stage, characterized by new blood vessel formation on the surface of the retina or the optic nerve. Severe visual loss can occur due to bleeding within the eye (vitreous hemorrhage) and retinal detachment.

Fluorescein Angiography

• Fluorescein angiography is a diagnostic test in which a very small amount of orange dye is injected into an arm vein and photographed as the dye passes through the retinal circulation. This technique is utilized to visualize both microaneurisms causing macular edema and neovascularization.

• In addition to optimizing control of blood sugar, blood pressure, and cholesterol, treatment of both macular edema and neovascularization utilizes a laser to seal leaking microaneurisms located within the macula, and more extensive scatter treatment throughout the retina to eliminate neovascularization. Laser therapy can be supplemented by injections of steroids and other medications placed within the eye.

Macular Edema, Before and After Treatment

Pan-Retinal or Scatter Photocoagulation

• The optimal time to treat is before symptoms develop. Often there are no early warning symptoms of diabetic retinopathy. It is essential to have regular, dilated examinations even if one isn’t having any problems with their eyes.
• More advanced stages of retinopathy, including vitreous hemorrhage and retinal detachment, which have caused a loss of vision, are treated by microsurgery (Vitrectomy).

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References

1. Centers for Disease Control, “Diabetes Disabling Disease to Double by 2050,” http://www.cdc.gov/nccdphp/publications/aag/ddt.htm, retrieved October 26, 2008.

Virginia Retina Foundation • 3301 Woodburn Road, Suite 204 • Annandale, Virginia 22003 USA

Telephone: +1 703 560 7300 • Fax: +1 703 560 7897 • Web: www.virginiaretina.org

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