Diabetic Retinopathy
Basics
Diabetic retinopathy is the inflammation and scarring of the retina (part of the eye) that occurs in people with diabetes. It causes loss of vision in adults with both type 1 and type 2 diabetes and is the most common cause of blindness in middle-aged Americans, accounting for at least 12 % of all new cases of blindness in this age group.
The longer you have diabetes, the more likely you are to develop diabetic retinopathy. After having diabetes for 30 years, the risk of blindness due to diabetic retinopathy is very high. However, strict control of diabetes can help prevent or delay the onset of vision loss. Regular eye doctor appointments and good control of blood pressure can also help preserve your vision. If you already have mild to moderate diabetic retinopathy, strict control of your diabetes can help keep your vision problems from getting worse.
Causes
Diabetic retinopathy is caused by having too much sugar in your blood on a regular basis (chronic hyperglycemia). Chronic hyperglycemia occurs when you do not control your blood sugar well enough. Medical researchers are not entirely sure why chronic hyperglycemia causes retinopathy, but they have some theories. Excess sugar may cause blood vessels to grow in the retina (swelling), or it could cause tiny blood clots to form in your eye. Both of these processes can damage your retina.
Symptoms
Many people do not have symptoms until late in the disease process, when it is difficult to treat the retinopathy. Symptoms may include the following: floaters, the sensation of a curtain falling across your vision, seeing unusual colors in your side vision, lowered visual acuity that glasses cannot correct, and the gradual development of blurred vision.
Risk Factors
Family history is an important risk factor. Having a close relative with diabetic retinopathy puts you at a much greater risk of developing this condition. Ethnicity is also a risk factor. African Americans and Hispanics are more likely than Caucasians to develop diabetic retinopathy. Researchers are not sure if this is due to genetic factors or to poorer diabetic control among certain ethnic groups.
Diagnosis
Your doctor will examine your eyes to look for changes in the retina. A general practitioner might be able to see some retinal changes with a simple office exam, but you will still need to see an eye doctor for a more thorough exam. Certain findings on an eye exam can lead to the diagnosis of retinopathy, including:
Your eye doctor may also do a diagnostic test called fluorescein angiography to look for leaky blood vessels in your eye. To do this, the doctor would inject dye into one of the veins in your arm. The dye travels to your retina, making leaky veins stand out so your doctor can determine which veins are damaged.
Your eye doctor may also order an optical coherence tomography (OCT) exam. This is an imaging test that does not involve any invasive procedures, such as an injection. The OCT exam takes pictures of your retina to look for findings such as a thickened retina and fluid in your retina.
Prevention and Screening
Treatment
Strict control of your diabetes is essential. Maintaining control of blood sugar levels throughout your lifetime can help prevent diabetic retinopathy. If you do develop diabetic retinopathy, controlling your blood sugar can help control the degree of eye damage you develop and may help preserve your vision. Regular eye doctor appointments are extremely important. If you have been diagnosed with type 2 diabetes, you should schedule yearly visits with your eye doctor. If you have been diagnosed with type 1 diabetes, you should start seeing an eye doctor every year within 3 to 5 years of your diagnosis. If you start to have vision problems while being treated for diabetes, you should notify your regular doctor. You could be developing retinal disease, and you should be referred to an eye doctor quickly.
If you have high blood pressure, it's essential to keep it under control. Maintaining a healthy blood pressure will also help preserve your vision.
Your doctor is the best source of information on the drug treatment choices available to you.
Your eye doctor or a retina specialist can do several procedures that can help improve your vision. One type is laser photocoagulation surgery, which involves the use of a special high-energy laser beam to create small burns that seal off leaky vessels. A specialist does this procedure. You will be given anesthetic eye drops to numb your eye, and sometimes anesthetic shots around your eyes. You can usually return home right after surgery, but you should not drive for 1 day due to blurred vision.
Panretinal photocoagulation is a more extensive type of laser treatment. For this procedure, the doctor uses laser therapy over most of your eye, only sparing your macula. This usually involves two or more laser treatments. Panretinal photocoagulation can cause side effects, including blurred peripheral vision and trouble with night vision.
If laser treatment is not effective, your eye doctor may try vitrectomy. This procedure involves removal of the vitreous, the clear gel between your retina and your eye's lens. Once the vitreous is removed, your eye doctor will perform laser photocoagulation.
There are no effective alternative medicine treatments for diabetic retinopathy.
Steroid injections into your eye, known as intravitreal steroids, may be effective. This treatment may be useful if you have macular edema, or swelling, leading to retinopathy. You may need to receive multiple injections to notice any improvement.
Strict control of diabetes is the key to preventing diabetic retinopathy. Following your doctor's advice, taking your medicine, and keeping your weight down are essential for controlling high blood sugar. If you have high blood pressure in addition to diabetes, maintaining a healthy blood pressure is also essential for preventing retinopathy.
Pregnant women who have diabetes sometimes experience a worsening of eye problems. If you are pregnant, you should have more frequent eye exams. Studies show that even though retinopathy may become worse during pregnancy, getting pregnant does not make you more likely to have worsening retinopathy in the long-term.
If you develop retinopathy, frequent eye exams, strict diabetes control, and medical treatment can all help preserve your vision.