Diabetes can affect many aspects of your health, including vision. Many of the estimated 24 million diabetics suffer from diabetes-related complications such as high blood pressure, heart disease and circulation issues. Like these conditions, the primary effect that diabetes has on vision is through your blood vessels. Diabetic retinopathy (or diseases of the retina) can cause the small blood vessels that nourish the retina, where light-sensitive tissue enables sight, to swell and leak. In some cases, diabetes can cause abnormal, weaker blood vessels to grow in the retina. Other conditions can also be accelerated in diabetes patients, including cataracts and glaucoma.
Types of Retinopathy
There are several stages of retinopathy that indicate the severity of the disease. Non-proliferative Retinopathy occurs in three stages: mild, moderate and severe. In the non-proliferative stage, existing blood vessels that provide nourishment to the retina are affected. In its mild form, only a minimal number of blood vessels are damaged. As non-proliferative retinopathy progresses to moderate and severe stages more vessels become affected, leading to small retinal hemorrhages, deposits, and areas of the retina are deprived of nutrients. In the severe stage, the retina sends signals to body to grow new blood vessels.
In the disease’s most advanced stage, Proliferative Retinopathy, the signals to build new blood vessels produce abnormal and fragile new blood vessels. These new blood vessels grow along the retina and onto the clear vitreous fluid that fills the eye. These blood vessels alone do not cause symptoms or vision loss, but because they are fragile, they can leak blood and fluid into the eye, which can cause vision loss and blindness.
There are often no symptoms or pain for diabetic retinopathy, so it is important for diabetics to have an annual eye exam. This eye exam should include a visual acuity test, a dilated eye exam and tonometry to measure the eye pressure. A visual acuity test can identify any vision changes caused by fluctuations in blood sugar levels. In the dilated eye exam, the doctor will place eye drops to open up the pupils to enable a thorough examination. Early signs of diabetic retinopathy include leaking blood vessels, retinal swelling, pale, fatty deposits on the retina, damaged nerve tissue and changes to blood vessels.
There are some symptoms that may indicate you may be suffering from diabetic retinopathy. You may notice spots in your vision, which are bits of blood dispersed in the vitreous humor in the center of the eye. Proliferative retinopathy can cause blood to leak into the center of the eye causing blurred vision. Macular edema or swelling of the macula —that part of the retina that provides sharp central vision—is one symptom caused by leaking fluid from the more advanced stages of retinopathy. Macular edema can cause blurry vision. Diabetics can be diagnosed with either macular edema or proliferative retinopathy or both.
According to the National Eye Institute, with timely treatment and proper follow-up care most people with diabetic retinopathy can reduce their risk of blindness by 95%. Diabetic non-proliferative and proliferative retinopathy are treated with lasers that are applied in two different ways, depending on the diagnosis.
A focal laser treatment is used when macular edema is present. This focuses a laser beam in a small area around the macula to place several hundred laser burns around the macula. This reduces the leakage that causes the macula to swell. You may need several treatments to control the leaking fluid.
A scatter laser treatment is used to treat proliferative retinopathy to shrink the numerous abnormal blood vessels that are formed in this stage of the disease. Because there are a high number of laser burns necessary to fully treat this stage, you may need to have several sessions of laser treatment.
Even though treatment is not a cure for retinopathy, detecting and treating diabetic eye disease with laser therapy can reduce the development of severe vision loss by an estimated 50% to 60%.
Vitrectomy is a surgical treatment used when a large amounts of blood have leaked into the vitreous. The treatment removes the vitreous gel in the center of the eye and replaces it with saline solution. A vitrectomy is typically performed under local or general anesthesia and may require a hospital stay. In a vitrectomy, a small incision is made in the eye, which allows the doctor to remove the vitreous humor that has become clouded with leaking blood. A saline solution quite similar to the vitreous humor is injected back into the eye to replace the fluid in the eye.
If you are diabetic, have any relatives with diabetes or if you experience any vision changes whatsoever, you should schedule a visit to your eye doctor for an early assessment. Early detection and treatment can slow the progression of diabetic retinopathy. Annual eye examinations can spot early signs of disease and prevent further vision loss.