November is diabetes awareness month. This articles focuses on diabetic retinopathy – the potentially blinding disease that affects the eye.
Diabetics who do not control their blood sugar levels are at a higher risk for diabetes complications that can damage the heart, kidneys, nerves, and eyes.
Blood vessels throughout the body are damaged by diabetes that is not under control including ones in the eyes. Diabetic retinopathy is a diabetes complication that affects the blood vessels in the eyes.
After several years of poorly controlled blood sugar, the blood vessels in the eye are damaged and not enough oxygen and nutrients are getting to the back of the eye. The body compensates for this by growing more blood vessels, but these newly created blood vessels are irregular, fragile, and weak, and they leak blood into the back of the eye.
The Two Types of Diabetic Retinopathy
Nonproliferative diabetic retinopathy (NPDR) means the walls of the blood vessels in your retinas are weakened. This can cause tiny bulges (microaneurysms) that protrude and sometimes leak fluid and blood into the surrounding retina.
This is the most common stage of diabetic retinopathy.
Nerve fibers in the retina and the central part of the retina (macular) may also swell. This is called macular edema and it requires treatment by corticosteroids, anti-VEGF injections or laser. The goal is to find the right modality to stop the macular edema.
Proliferative diabetic retinopathy (PDR) is the advanced form of diabetic retinopathy. Proliferative means that the new, abnormal, fragile, and weak blood vessels have grown somewhere inside the eye. This can cause bleeding into the vitreous, diabetic retinal detachment or neovascular glaucoma.
The blood vessels are growing (proliferating) because the retina is starved for oxygen and is seeking a way to find it.
If left untreated, the weakened blood vessels will grow from the retina into the vitreous (the gel-like fluid that fills the eye) and can detach the retina. The overgrowth of blood vessels also can cover the area of the eye that drains fluid which will greatly increase eye pressure, which in turn damages the optic nerve. This cascade of events can cause severe vision loss.