Diabetes and the eye

Diabetes and eye

Diabetes is a worldwide epidemic. In Canada, 8% of the population is diabetic! This disease affects the small blood vessels everywhere in the body, including the brain, your heart, your kidneys, and your eyes. There are many ocular manifestations of diabetes.

What are the types of Diabetes?


  • Type I Diabetes - this is an autoimmune disease, whereby the body’s immune system attacks the pancreas (organ where insulin is made). This type of diabetes appears in school age children. Without treatment (insulin replacement), this disease is fatal.


  • Type II Diabetes - this disease is very different from type I diabetes. It is a largely preventable disease that occurs in adulthood, due to obesity. This disease is due to tissues in the body becoming less sensitive to insulin. Adopting a healthier lifestyle, including weight loss, can be curative.

What is diabetic eye disease?

As diabetes affects small blood vessels in the body, most of the ocular damage occurs at the back of the eye in the retina (the “film of the camera”). The small blood vessels are damaged, which leads to a lack of oxygen to the seeing eye tissues. This is called Diabetic Retinopathy. It is important to see your eye doctor regularly if you are diabetic, as vision-saving treatment may be required without you being aware.

Why does diabetic retinopathy cause blurry vision?

  • Diabetic Macular Edema - the damage to capillaries (small blood vessels) in the retina, makes them leaky. This leakage of fluid into the area of central vision causes thickening of the “film of the camera” and is the most common cause of blurry vision due to diabetes.
  • Vitreous Hemorrhage - damage to small blood vessels from diabetes results in a lack of oxygen to the back of the eye. In response to this lack of oxygen, the back of the eye grows new blood vessels. Unfortunately, these blood vessels are not normal, and are very fragile (neovascularization). They break very easily causing bleeding, which results in a sudden loss of vision. Without treatment, the abnormal blood vessels undergo scarring, which can cause a retinal detachment. This is end stage diabetic eye disease and usually has a poor prognosis.

How is diabetic eye disease treated?

Macular edema (the most common cause of loss of vision in diabetics) is treated with monthly injections of an anti-VEGF (vascular endothelial growth factor) drug. These are special medicines (covered for people over the age of 65) that make the small blood vessels less leaky. When the fluid in the retina drys up, vision improves. These medicines also prevent the growth of the abnormal fragile blood vessels that can bleed.  Sometimes laser treatment may also be needed to the back of the eye.

What can I do to prevent vision loss from diabetes?

Type II diabetes is the most common form of diabetes, and is largely preventable. Losing weight is the single most important thing you can do to help yourself.

  • Eat less meat, and more fruits and vegetables (watch “Fork over Knives” on Netflix)
  • Lose weight
  • Exercise - find something you enjoy. You MUST make this fun. (dance classes, boxing, rowing, walks in the country)
  • Get motivated - find what makes you motivated to change your lifestyle (do you want to play with grandchildren? Do you want to actively enjoy life again?) Use this motivation to make these changes to your life
  • See your eye doctor regularly