Intricate and complex, the eyes take in and process light and communicate information to the brain through electronic impulses. Several diseases and conditions - viral, bacterial, and genetic - affect the eyes and their ability to function properly. Any sign of unusual eye symptoms should prompt a visit with an eye care professional.
Cytomegalovirus (CMV) Retinitis
Associated with acquired immunodeficiency syndrome (AIDS), this disease also affects people whose immune systems have been compromised for other reasons like chemotherapy or bone marrow transplant. The virus invades the retina and damages photoreceptor cells, causing floaters, blurry vision, flashes, and/or decreased peripheral vision. Left untreated, CMV retinitis leads to detached retina and blindness.
An eye condition in which the cornea thins, weakens, and loses its normal round shape, keratoconus causes astigmatism and nearsightedness. Though the exact cause is not yet known, research has shown that an imbalance in enzymes within the cornea might cause keratoconus. No cure exists for keratoconus, but effective methods of treatment which slow its progression and reduce symptoms have been developed.
Fuchs' Corneal Dystrophy
An inherited disease, Fuchs' corneal dystrophy causes endothelial cells which regulate fluid in the cornea to die. This leads to corneal edema (swelling). Symptoms include glare, blurred or distorted vision, painful blisters on the cornea, a cloudy or hazy cornea, corneal swelling, and corneal thickening.
A genetic eye disorder, macular dystrophy damages the photoreceptor cells located on the macula (the center of the retina), leading to a loss of central vision. Central vision is used to look straight ahead and is necessary for activities such as reading, driving, and recognizing faces. There are two types of macular dystrophy: Best disease, which affects children, and adult onset macular dystrophy, which occurs in adulthood.
Retinitis Pigmentosa (RP)
A rare, inherited disease, RP causes the photoreceptor cells in the retina to progressively degenerate. This degeneration first narrows the field of vision and leads to decreased night vision. Eventually, photoreceptors deteriorate so extensively that the disease causes near blindness with only slight peripheral and a small area of central vision remaining.
A form of inherited macular dystrophy which affects children and young adults, Stargardt disease is characterized by the death of photoreceptor cells on the macula (the center of the retina). Sufferers usually lose central vision while peripheral vision remains intact.