Diabetes is a serious condition in which a person experiences high levels of blood sugar over an extended period of time. This can happen for one of two reasons: Either the pancreas does not produce enough insulin, a hormone that regulates the level of sugar in the blood, or the pancreas does produce enough insulin, but the cells of the body fail to respond properly to the insulin.
Many complications related to diabetes may arise as a result of improper maintenance of one's blood sugar or blood pressure. Among the most serious of these conditions is an eye condition called diabetic retinopathy. This condition occurs when blood vessels change in the retina, in some cases causing blood vessels to swell or leak fluid. Blood vessels may also close off completely, or a process called neovascularization may take place, in which new and abnormal blood vessels grow on the surface of the retina, causing it to wrinkle, seriously damaging your vision.
When blood sugar levels get too high for too long, it is possible that damage will be done to the blood vessels that supply blood to the retina. Over time this damage will cause the blood vessels to begin leaking fluids, causing swelling and other damaging effects to the eye. This is called non-proliferative diabetic retinopathy (NPDR), and is the earliest form of the condition. Dr. Lior Koppel of EyeKrafters Medical Optics in South Plainfield, NJ explains, “Although most people with NPDR do not experience any ill effects to their vision, a number of serious complications are possible in which NPDR could do significant harm. Macular edema is a major complication related to NPDR. This is a swelling or thickening of the macula caused by fluid leaking from the retina's blood vessels, hindering the macula's ability to function properly. The macula is the small part of your retina responsible for your central and fine-detail vision, so if the macula is prevented from working properly, it can very seriously affect your vision. A blurring of your vision may also occur. This is called macular ischemia, and is caused by the closure of small blood vessels in your macula, causing your macula to be starved for oxygen.”
Another, more serious form of diabetic retinopathy is known as proliferative diabetic retinopathy (PDR). This mainly occurs when many of the blood vessels in the retina become closed off, which starves the retina of a great amount of blood and oxygen. This is when neovascularization occurs. Starved for oxygen, and in an attempt to supply itself with the blood it is lacking, the retina begins growing new blood vessels. These new blood vessels are often also accompanied by scar tissue which may later shrink, possibly causing the retina to wrinkle and be pulled from its normal position.
This is a condition called traction retinal detachment and can seriously distort your vision, and cause more serious vision loss if the macula or large areas of the retina become detached. Dr. Koppel adds, “A condition called neovascular glaucoma may also result from severe neovascularization. This happens when neovascularization occurs in the colored part of the eye, called the iris, blocking the normal flow of fluids out of the eye and causing fluid pressure in the eye to rise. This can cause severe damage to the optic nerve, the bunch of nerves at the back of the eye that feeds visual information to the brain, and severely damage your sight.”
If your eyesight periodically changes from blurry to clear, or you are experiencing dark spots or blank areas in your vision, these may be signs of diabetic retinopathy. You may also experience what seem to be spots, dots, or cobweb-like strings floating in your vision, called floaters.“Because of the potentially irreversible damage that can be done to the eye, and the difficulty of treating diabetic retinopathy, the best treatment is to prevent it altogether,” warns Dr. Koppel, “Keeping your blood sugar under control is a very important part of this, but it is just as important to have frequent comprehensive eye exams so that if signs of retinopathy emerge, treatment can be begun immediately.”