Understanding Diabetic Retinopathy
People with type-2 diabetes usually have signs of eye
problems when diabetes is diagnosed. In this case, control of blood sugar,
blood pressure and blood cholesterol with diabetes have an important role in
slowing the progression of retinopathy and other eye problems. Types of
Retinopathy in Diabetes:
The retina is a group of specialized cells that convert
light as it enters though the lens into images. The eye nerve or optic nerve
transmits visual information to the brain.
Diabetic retinopathy is one of the vascular (blood-vessel related)
complications related to diabetes. This diabetes eye problem is due to damage
of small vessels and is called a "microvascular complication." Kidney
disease and nerve damage due to diabetes are also microvascular complications.
Large blood vessel damage (also called macrovascular complications) includes
complications like heart disease and stroke.
The microvascular complications have, in numerous studies,
been shown to be related to high blood glucose levels. You can reduce your risk
of these eye problems in diabetes complications by improving your blood sugar
control. Diabetic retinopathy is the leading cause of irreversible blindness in
industrialized nations. The duration of diabetes is the single most important
risk for developing retinopathy. So the longer you have diabetes, the greater
the risk of this very serious eye problem. If retinopathy is not found early or
is not treated, it can lead to blindness.
People with type-1 diabetes rarely develop retinopathy
before puberty. In adults with type 1 diabetes, it is also rare to see
retinopathy before five years' duration of diabetes. The risks of retinal
damage increase with progressive duration of diabetes. Intensive control of
blood glucose levels will reduce your risks of developing retinopathy. The
DCCT, a large study of people with type 1 diabetes showed that people with
diabetes who achieved tight control of their blood sugars with either an
insulin pump or multiple daily injections of insulin were 50%-75% less likely
to develop retinopathy, nephropathy (kidney disease) or nerve damage (all
microvascular complications).
#1 - Background retinopathy. Sometimes the blood vessel
damage exists, but there is no vision problem. This is called background
retinopathy. It's important to carefully manage your diabetes at this stage to
prevent background retinopathy from progressing to more serious eye disease.
#2 - Maculopathy. In maculopathy, the person has developed
damage in a critical area called the macula. Because this occurs in an area
that is critical to vision, this type of eye problem can significantly reduce
vision.
#3 - Proliferative retinopathy. New blood vessels start to
grow in the back of the eye. Because retinopathy is a microvascular
complication of diabetes, a disease of small vessels, this type of retinopathy
develops because of an increasing lack of oxygen to the eye from vascular
disease. Vessels in the eye are thinned and occluded and they start to remodel.
Here, it is important to address the risks factors that can
worsen the occluded vessels. Smoking cessation, hypertension control,
cholesterol management and glucose control must take place in order to stop the
progression of new vessels from forming into the orbit of the eye. These are
fragile vessels that can bleed and eventually cause a clot to form in the
orbit, which scars and causes detachment of the retina. This eventually leads
to irreversible vision loss.
Treatment of diabetic retinopathy may involve laser
procedures or surgery. In a study of people with diabetes with early
retinopathy, laser therapy to burn the fragile vessel resulted in a 50%
reduction of blindness.
To prevent retinopathy with diabetes, have your eye doctor
screen your eyes annually. Women with diabetes who later become pregnant should
have a comprehensive eye exam during the first trimester and close follow-up
with an eye doctor during the rest of their pregnancy to avoid serious eye
problems with diabetes. (This recommendation does not apply to women who
develop gestational diabetes, since they are not at risk for retinopathy.)
