Age-Related Macular Degeneration
Macular degeneration is the leading cause of irreversible vision loss in elderly Americans. It is more common in people of northern European ancestry. It tends to run in families. It is a progressive condition associated with aging. The macula is the central specialized area of the retina associated with color vision and reading. Macular degeneration does not affect peripheral vision and does not lead to total loss of vision. In its advanced forms it can make it difficult to read and impossible to drive. It always affects both eyes. There is no cure.
Most macular degeneration is classified as the dry form. This label means that there is no associated bleeding or leakage in the macula. The main symptoms are blurred vision or blind spots in the vision. These symptoms are slowly progressive and can ultimately lead to legal blindness. The only proven treatment is a combination of vitamins called the AREDS 2 formula. This treatment has been shown to reduce the rate of vision loss. Current research is focused on slowing or stopping the progression of the disease and vision loss.
About 10-20% of macular degeneration is classified as the wet form. In this form there is often a rapid onset of distortion and blurring of the vision in one eye due to leakage or bleeding in the macula. If diagnosed early, currently available drugs are quite effective in maintaining or improving vision when injected into the eye. These treatments are not a cure and must be continued indefinitely to maintain vision. When one eye progresses to the wet form of the disease there is an increased risk of about 10% annually for the other to develop the same condition. Current research is aimed at reducing the number of treatments and improving vision.
Diabetic Retinopathy and Diabetic Macular Edema
Diabetic retinopathy is the leading cause of vision loss in working age Americans. It is a common cause of permanent visual impairment in middle age. It is a complication of diabetes. The risk of developing it is related to length of diabetes and poor diabetic control. The diagnosis of diabetic retinopathy increases the risk for developing the other complications of diabetes, in particular diabetic neuropathy and diabetic kidney disease. Diabetes type two tends to run in families. Sometimes the diagnosis of diabetic retinopathy is the first sign of diabetes. There is no cure for diabetic retinopathy.
The first stage of diabetic retinopathy is called non-proliferative diabetic retinopathy. It can be asymptomatic and is most commonly found on a routine retinal exam. Diabetes damages the fragile blood vessels in the retina leading to hemorrhages and leakage. Current treatments can reduce the blood vessel damage when the drugs are injected into the eye. Current research is directed at developing longer lasting drugs.
Chronic leakage of the blood vessels can lead to diabetic macular edema. This is the leading cause of vision loss from diabetic retinopathy. It causes a progressive blurring of the vision that is not correctable with glasses. This can be successfully treated with current drugs about 60% of the time. Current drugs are injected into the eye on a monthly basis as needed. It is commonly bilateral, but may not affect both eyes at the same time. Current research is directed at developing more effective treatments.
The most advanced stage of diabetic retinopathy is called proliferative diabetic retinopathy. This form of retinopathy is associated with the growth of abnormal blood vessels in the retina. It is associated with a high risk of sudden vision loss due to bleeding into the vitreous or retinal detachment. Current treatments are effective at stopping the bleeding. The treatments include drugs that are injected into the eye monthly and laser surgery. Retinal detachments are treated with surgery. Current research is directed at developing longer lasting drugs.
Retinal Vein Occlusions
Retinal vein occlusions are the third most common retinal disease leading to loss of vision. They are associated with aging of the blood vessels. This can be exacerbated by hypertension and diabetes. Glaucoma is also a risk factor. Current treatments are successful in improving vision about 75% of the time. The treatments include drugs that are injected into the eye and laser surgery. Current research is directed at developing more effective and longer lasting drugs.
Macular telangiectasia type 2 is a rare congenital retinal disease that usually manifests itself in young adults or middle age. It can lead to blurred vision in one or both eyes. There is currently no treatment.