In every issue of WebMD the Magazine, we ask our experts to answer readers' questions about a wide range of topics. In our July/August 2012 issue, we asked WebMD's diabetes expert, Michael Dansinger, MD, about the link between diabetes and poor sleep.
Q: I have diabetes, and I'm not sleeping well. Are the two related, and what can I do?
A: Yes, people with diabetes often have reduced sleep quality and quantity. Sleep apnea, medications, lack of exercise, and abnormal glucose and hormone...
The retina is a light-sensitive nerve tissue at the back of the eye. As light enters the front of the eye, the retina converts the light rays into electrical impulses that travel along the optic nerve to part of the brain called the visual cortex. The brain then combines images sent from both eyes to interpret them as a single, three-dimensional image. This allows us to perceive depth and distance. Without the retina, the eye cannot communicate with the brain, making vision impossible.
In the early stages of diabetic retinopathy, called nonproliferative retinopathy, these blood vessels leak fluid and distort sight. In the more advanced stage of diabetic retinopathy, called proliferative retinopathy, fragile new blood vessels grow around the retina and in the vitreous humor (a clear substance that fills the eye). If left untreated, these blood vessels may bleed, clouding vision or scar detaching the retina.
Anyone with diabetes -- both type 1 or type 2 diabetes -- is at risk of developing diabetic retinopathy. However, the type of diabetes a person has, how often their blood glucose fluctuates, how well controlled the sugars are, and how long a person has had diabetes all affects his or her risk. The better you control blood sugar levels, the lower your risk.
The National Eye Institute estimates that 40%-45% of all Americans with diabetes are affected by diabetic retinopathy, and 24,000 of them go blind each year.
What Happens if Diabetic Retinopathy Is Not Treated?
In untreated diabetic retinopathy, scar tissue that forms on the back of the retina as a result of a contraction of the new blood vessels can cause the retina to pull away from the back of the eye. This is called a retinal detachment. Retinal detachment can cause permanent blindness if left untreated.
Diabetic retinopathy can also cause macular edema. The macula is the inner part of the retina that allows for detail to be seen. When fluid from blood vessels leaks into the macula, it can swell making vision blurry.