Wet macular degeneration is a chronic eye disorder that causes blurred vision or a blind spot in your visual field. It's generally caused by abnormal blood vessels that leak fluid or blood into the macula (MAK-u-luh). The macula is in the part of the retina responsible for central vision.
Wet macular degeneration is one of two types of age-related macular degeneration. The other type — dry macular degeneration — is more common and less severe. The wet type always begins as the dry type.
Early detection and treatment of wet macular degeneration may help reduce vision loss and, in some instances, recover vision.
Wet macular degeneration symptoms usually appear suddenly and worsen rapidly. They may include:
- Visual distortions, such as straight lines seeming bent
- Reduced central vision in one or both eyes
- Decreased intensity or brightness of colors
- A well-defined blurry spot or blind spot in your field of vision
- A general haziness in your overall vision
- Abrupt onset and rapid worsening of symptoms
Macular degeneration doesn't affect side (peripheral) vision, so it rarely causes total blindness.
No one knows the exact cause of wet macular degeneration, but it develops in people who have had dry macular degeneration. Of all people with age-related macular degeneration, about 10 percent have the wet form.
Wet macular degeneration can develop in different ways:
- Vision loss caused by abnormal blood vessel growth. Sometimes abnormal new blood vessels grow from the choroid under and into the macula (choroidal neovascularization). The choroid is the layer of blood vessels between the retina and the outer, firm coat of the eye (sclera). These abnormal blood vessels may leak fluid or blood, interfering with the retina's function.
- Vision loss caused by fluid buildup in the back of the eye. When fluid leaks from the choroid, it can collect between the thin cell layer called the retinal pigment epithelium and the retina. This may cause a bump in the macula, resulting in vision loss or distortion.
Factors that may increase your risk of macular degeneration include:
- Age. This disease is most common in people over 50.
- Family history. This disease has a hereditary component. Researchers have identified several genes related to developing the condition.
- Race. Macular degeneration is more common in white people.
- Smoking. Smoking cigarettes or being regularly exposed to smoke significantly increases your risk of macular degeneration.
- Obesity. Research indicates that being obese increases the chance that early or intermediate macular degeneration will progress to a more severe form of the disease.
- Cardiovascular disease. If you have diseases that affect your heart and blood vessels, you may be at higher risk of macular degeneration.
People whose wet macular degeneration has progressed to central vision loss have a higher risk of depression and social isolation. With profound loss of vision, people may see visual hallucinations (Charles Bonnet syndrome).