What Is Ranibizumab Used For? -- An Overview
What Is Macular Degeneration?
Age-related macular degeneration (AMD, or just macular degeneration) is a common eye disease associated with aging. It blurs the sharp, central vision you need for "straight-ahead" activities, such as reading or driving
(see Macular Degeneration and Driving). The
causes of macular degeneration are unknown. However, certain risk factors (such as smoking and obesity) increase the likelihood of developing it. Macular degeneration may be genetic also to some extent
(see Macular Degeneration Genetics).
If the loss of these light-sensing cells in the macula becomes great, people may see a small (but growing) blind spot in the middle of their field of vision. Over time, the blurred spot may get bigger and darker, taking up more of your central vision. You may have difficulty reading or recognizing faces until they are very close to you.
There are two
types of macular degeneration. About 90 percent of people with the disease have what's known as the "dry" type, and the remaining 10 percent have the "wet" type. However, wet macular degeneration accounts for 90 percent of all blindness associated with the disease.
In wet macular degeneration, new blood vessels grow behind the macula. Because these new blood vessels tend to be fragile, they will often leak blood and fluid under the macula. This causes rapid damage to the macula, which can lead to the loss of central vision in a short period of time. Wet
macular degeneration symptoms include straight lines appearing crooked and a blind spot in the center of your vision.
With wet macular degeneration, loss of central vision can occur quickly. This is a more advanced form of the disease, and is more severe than
dry macular degeneration.
