Macular degeneration, often referred to as age related macular degeneration (AMD) is a leading cause of vision loss in people 55 and older in the United States, affecting approximately 30-50 million people globally. Stargardt disease is a form of macular degeneration found in children and young adults but is relatively rare. AMD causes loss of central vision. It is a progressive condition, which does not result in total blindness, but can greatly impact one’s ability to function. Symptoms include distorted vision, difficulty adjusting vision when moving from a dark to bright setting or vice versa, decreased visual acuity, central scotomas (missing areas of vision) and difficulty identifying colors. Therefore, common everyday tasks such as reading, driving and recognizing people’s faces can become difficult.
The two main types of macular degeneration are referred to as dry and wet. Approximately 90% of people with AMD have the dry form.
The "dry" form of macular degeneration is caused by slow break down light sensitivity cells in the macula. This may lead to distortion of vision and in advanced stages a person can experience blind spots in their central vision or total loss of central vision. The cause is unknown, but the progression of vision loss tends to be significantly slower than that in the wet form. At this time, there is no treatment for dry AMD.
The "wet" form of macular degeneration is caused by the growth of abnormal fragile blood vessels underneath the retina which often leak blood and fluid into the retina causing distortion and scarring of the retina. This can result in rapid and severe vision loss. There are some treatment options to slow down the progression of wet macular degeneration. These include anti-angiogenesis drugs, photodynamic therapy and laser therapy.
Risk factors for age related macular degeneration include age, race (more common in Caucasians) and family history.
Practical Implications
A person who is dealing primarily with AMD will most likely be able to move around, communicate and complete many daily tasks independently or with some accommodations because they will compensate for their visual condition through use of their residual vision and their hearing. For example, a person with macular degeneration may not see a new person enter the room, but they may hear them or see other people looking toward the door.
A person who has AMD in combination with a hearing loss or deafness faces a greater challenge as they can’t rely on their hearing to compensate for their vision loss. This can result in mobility challenges, communication breakdowns and the inability to complete daily tasks. For people who are Deaf who communicate through sign language, AMD can cause serious issues with receptive communication as there may be several spots in their visual field where they can’t see the signs. Strategies such as tracking or tactile sign language may help ensure clear communication