Diabetic Eye Disease
Diabetes can affect the eyes as a long term complication of the disease. The most common and sight threatening complication affects the ‘retina’ which is the main part of the eye. This disease is called Diabetic retinopathy (DR)
How serious is this disease?
DR if not treated on time can result in permanent blindness. It is a common cause of blindness in the western world and rapidly becoming common in our country.
How does vision loss occur?
Vision loss commonly occurs due to bleeding into the eye from the growth of new blood vessels or from the swelling of retinal tissues. Other causes include retinal detachment, glaucoma, cataract, infections and others.
Who is likely to get diabetic retinopathy?
All diabetics can eventually develop DR. The chances of getting the disease increase with the following:
- Duration of diabetes. The longer one has had diabetes, the higher the likelihood of developing retinopathy.
- Poor glucose control. Usually most diabetics do not control their blood glucose levels in the early course of the disease resulting in a gradual damage to the blood vessels the effects of which show up later in life.
- High blood pressure. If blood pressure is not well-controlled then this will increase your risk of developing retinopathy.
- Nephropathy (kidney disease) kidney and eye complications often go hand in hand
- Anemia decreases the oxygen carrying capacity of the blood worsening the amount of oxygen reaching the retina.
- Smoking or Tobacco in any form
- Other risk factors include pregnancy, obesity and having high cholesterol levels.
What I can I do to prevent blindness from DR?
DR is a difficult disease to treat and best results are achieved when diagnosed early and treated at the right time. For this your retina should be checked as soon as you are diagnosed with diabetes and yearly thereafter or as your doctor advises. Also keeping a strict control of blood sugars/BP and other factors mentioned above will help.
If I control my blood sugars now will my eyes become alright?
Controlling blood sugars now will certainly help to some extent but cannot completely reverse the damage that has already taken place. The effect of the damage done over years keeps causing problems. It is like a smoker who has smoked for many years and has spoilt his lungs. Stopping smoking now will not make the damaged lungs better but will prevent further destruction.
When should I get my eyes examined?
All diabetics must undergo a thorough eye examination once a year. The examination must include a check of the vision, eye pressures and examination of the retina after dilation of the pupils with eye drops.
Do I need to get myself examined even if I have perfect vision?
Yes, all diabetics must be examined even if they have perfect vision as there can be Diabetic Retinopathy without loss of vision. Also it is easier to prevent loss of vision than to bring back lost vision.
What Investigations (special eye tests) may be required?
The following investigations may be ordered by your doctor to understand your disease better and to plan the treatment.
- Fluorescein Angiography (FFA)
- Optical Coherence Tomography (OCT)
- Ultrasonography (USG) in patients with vitreous hemorrhage.
What are the treatment options?
Depending on the severity of retinopathy that you have the following treatment options may be recommended. One or more may be advised at the same time.
Laser photocoagulation is advised:
To prevent ‘new blood vessel’ formation
To treat or destroy formed ‘new blood vessels”
To decrease the swelling of the retina
While undergoing treatment with lasers it is important to remember that:
It is done in the OPD and is not a surgery.
Use of lasers may not result in visual improvement, but is done to prevent further drop in vision.
Multiple sittings may be required depending upon the severity of the disease.
Injections of drugs into the eye help to decrease the swelling of the retina and to dry up the new vessels. The effect of these injections is only ‘temporary’ and gives time for more permanent treatments (laser, vitrectomy) to be effective. These injections are:
Pegaptanib Sodium (Macugen)
Vitreo retinal surgery: In advanced cases of Diabetic Retinopathy, laser photocoagulation may not work and surgery may be required.
Is the treatment of diabetic retinopathy required again and again?
Yes. Since the disease does not leave the patient it can again and again cause problems which have to be treated from time to time. All patients need regular follow up throughout their lives. Further investigations and treatment are required from time to time as decided by the doctor.