Many eye diseases affect different parts and functions of the eye. The most commonly diagnosed eye diseases are cataracts, glaucoma, retinal detachment, diabetic retinopathy, and macular degeneration.
Cataracts are a common cause of impaired vision. The condition develops gradually as people age. The onset of cataracts is usually a chemical process associated with aging that causes the human lens to be less transparent. This affects the vision to the point where only light and dark colors are seen. Eventually cataracts can result in vision loss. There are many reasons why cataracts occur besides aging, such as lens injury, genetics, cigarette smoking, and diabetes. Cataracts are usually treated by surgery which involves removing the damaged lens and replacing it with an artificial lens.
Glaucoma is a broad name for all the eye diseases that cause an increase in the pressure of the fluids in the eye. The fluid called humor is what holds the shape of the eye and also serves as the nutrient supply for both the lens and the cornea. The ciliary body in the eye supplies the humor to the eye and when there is excess humor, it drains out the front of the eye. With glaucoma, the fluid does not drain away causing the internal eye pressure to increase, which puts pressure on the optic nerve and the blood vessels supplying the eyes with nutrients, effectively blocking them. The lack of nutrition damages the eye causing cells to slowly die off, resulting in a loss of vision and eventually blindness. Symptoms include blurry side vision, severe eye pain, seeing floaters, headaches, and nausea. Glaucoma eye diseases are usually diagnosed by the time the patient has already suffered irreversible vision loss but for those fortunate enough to be diagnosed early, treatment is possible.
With retinal detachment, the retina moves away from the back of the eye. This disease’s onset can be sudden or occur chronically. Either way, retinal detachment can lead to impaired vision, and eventually to total blindness. Retinal detachment can be a result of aging or a genetic predisposition. Symptoms include a loss of certain vision fields, floaters, and deteriorating vision. If diagnosed early, the retina can be reattached deterring any further vision loss.
Diabetic retinopathy, as the name suggests, is a side effect of diabetes mellitus. Diabetes occurs when an individual cannot regulate blood glucose levels. Chronic exposure to high glucose levels weakens the blood vessels in the eye, causing them to leak blood. The hemorrhaging of the weakened vessels causes scaring that can eventually lead to vision loss. The increased glucose levels also affect the eye nerve cells.
The most common macular degeneration is the age related disease. This eye disease, which affects the macula (central retina), is the most common reason for vision loss in the United States in the over-50 age group. The disease is caused by the hardening of the arteries that feed the retina, which in turn slowly cuts off nutrition to the retina. The result can be either the complete loss of central vision or vision distortion. The disease does not cause complete vision loss. There is no treatment for this disease but laser photocoagulation or photodynamic therapy may slow down the vision loss process if the condition is diagnosed early enough.
The best way to prevent vision impairment and loss is to have regular eye exams. If symptoms occur such as sudden changes in vision, severe eye pain, fluid leakage from the eye, or inflammation, seek immediate medical attention.