What is the connection?
Diabetes can affect almost any part of the eye, and is one of the leading causes of blindness worldwide. The most common ways of affecting the vision is when diabetes causes cataracts, but even more devastating is when diabetes affects the posterior segment of the eye, which is termed diabetic retinopathy / maculopathy.
The risk of developing diabetic retinopathy increases with the length of the illness, and affects up to two-thirds of all diabetics after 15 years. Almost 90% of diabetics will have some degree of retinopathy after 40 years.
Even though the risk increases with the length of the disease, it has been shown that tight glycemic control decreases the risk of progression as well as the need for laser intervention. Therefore it is off utmost importance to all diabetics to make sure that their blood sugar is well controlled, and that their HbA1C levels are checked by their attending health care providers. All diabetics should also have annual dilated eye examinations in order to detect damage early and treat appropriately.
What exactly is diabetic retinopathy?
The complete pathophysiological mechanism is very complex, but in general terms, diabetes causes changes and damage to the blood vessels in the eye, that are responsible for nourishing the retina (light sensitive cells lining the back of the eye). Over the years the damage to the vessels causes decreases blood flow to certain parts of the retina and leakage, and can even lead to the formation of new vessels that can also leak and cause bleeding inside the eye.
What are the symptoms of diabetic retinopathy?
In patients with early diabetic retinopathy (non-proliferative diabetic retinopathy), there are mostly now symptoms except possibly for a mild deterioration of their vision. If the damage becomes more severe (proliferative diabetic retinopathy), and the vessels start leaking, bleeding inside the eye can lead to blurred / decreased vision and floaters. These floaters can be caused by the blood in the back of the eye (vitreous haemorrhage) or may indicate that there is traction on the retina, which can lead to a retinal detachment.
Some patients have no bleeding but still very poor vision. This can be caused by leakage of fluid at or around the macula (see anatomy of the eye), called macular edema.
How can diabetic retinopathy be treated?
Proliferative diabetic retinopathy can be treated by the use of a powerful laser that thins out the retina and increases the blood supply to the viable retina. Macular edema can also be treated by a different type of laser that increases the reuptake of the fluid that has leaked. Another treatment option includes the use of a specific type of agent that is injected into the eye to decrease the amount of swelling at the macula, and is usually followed by laser therapy. All these treatment options can mostly halt the progression of damage to the retinal cells, if detected early. It is therefore crucial that any form of diabetic retinopathy be followed up more regularly by the eye care professional in order to monitor progression and response to treatment.
In very severe cases, when vitreous haemorrhage does not clear, or if a retinal detachment occurs, surgical intervention is required in the form of a vitrectomy. This must be done by specialized vitreo-retinal surgeon in theatre.
Please feel free to contact the rooms and make an appointment with any inquiries regarding your eye condition, and to discuss any of the treatment options.