Diabetes is a medical condition that results from the body’s inability to handle sugar that is ingested from food and results in abnormalities in the level of sugar in the bloodstream.   In Type 1 or juvenile-onset diabetes there is a lack of the hormone insulin, which is a substance that enables the body’s cells to process the sugar that is digested from food.  Adult- onset or type 2 diabetes results from the body’s resistance to insulin’s effectiveness.  Less commonly, diabetes results from other conditions, such as the use of certain medications. [www.diabetes.org/]

Diabetes can affect the eye in several ways.  It can cause changes in the retina, the structure in the back of the eye that is analogous in function to the film in a camera.  Retinopathy refers to changes in the retina that can occur as a result of diabetes.  Persons who are diabetic are also at greater risk for developing glaucoma.  Diabetics can also develop cataracts at an earlier age than non-diabetics.  All of these conditions, if left undiagnosed and untreated, can result in a decrease or loss of vision. [diabetes.diabetesjournals.org/]

Changes in blood sugar levels can cause blurring and fluctuations of vision.  When the blood sugars are very high, as can occur in newly diagnosed adult-onset diabetes, the vision can be very blurry.  Then, after the blood sugars have normalized with treatment, the blurry vision resolves.  It is not uncommon for the vision to be blurry and fluctuate for several weeks until the blood sugars are controlled.  If you have been newly diagnosed with adult-onset diabetes are and are experiencing blurry vision, it is not uncommon for your eye care provider to recommend waiting several weeks after the blood sugars have returned to a normal level before checking to see if a glasses prescription is necessary to improve your vision.  Similarly, if you have diabetes and are experiencing the new onset of blurry vision, it is a good idea to check your blood sugar to see if it is abnormal.

Diabetes can damage the retina of the eye.  This damage occurs slowly and you may not be aware of the damage at first.  The small blood vessels of the eye, called capillaries, can swell and weaken.  The blood vessels then become clogged and can not let enough blood through.  All this can occur without you being aware of the problem.  This is why it is important to have yearly examinations.

What Happens As Diabetic Retinal Problems Worsen?

As more capillaries close-off the body attempts to increase blood flow to the retina by growing new vessels.  These vessels are abnormal and bleed and leak fluid.  This can cause hemorrhage inside the eye and also cause some tissue to form and pull the retina away from the back of the eye.

Diabetic retinal disease can cause vision loss in several different ways.  Abnormal blood vessels can leak fluid and cause the retina to increase in thickness.  This is called diabetic macular edema.  When the retina is swollen vision will decrease.  Abnormal blood vessls can also cause retinal and vitreous bleeding.  Vision can also be lost from ischemia, that is loss of blood flow to the retina.

What Can Be Done To Prevent Diabetic Retinopathy?

You need to keep your blood sugar normal by diet, exercise and medication if needed.  You need to check your blood sugar at least once per day and sometimes four times per day.  You need to keep your blood pressure normal also.  If you are pregnant have an eye examination during your first trimester.  Early detection of diabetic retinopathy is important as early stages can be reversed with strict control

Persons with diabetes are also at greater risk of developing glaucoma.  Glaucoma is an eye condition where there is damage to the optic nerve, which is the nerve that connects to the brain and allows us to see.  The only way to diagnose glaucoma is with regular eye exams.  Glaucoma, if detected early, can be treated and vision can be preserved.

Diabetics can also develop cataracts, and they can occur at an earlier age that in non-diabetics.  A cataract occurs when the lens of the eye becomes cloudy.  Cataracts can be removed with surgery.  However, persons who have diabetes and diabetic retinopathy can experience worsening of the retinopathy after cataract removal.  Again, routine eye exams are necessary to prevent complications in the eye associated with diabetes.

In summary, if you have diabetes, make sure you have your eyes examined regularly, usually once a year.  Sometimes your eye care provider may recommend more frequent eye exams.  This is the best way to prevent diabetes -related complications in the eye.