Age-Related Macular Degeneration

1. Home
2. Conditions
3. Age-Related Macular Degeneration

Age-Related Macular Degeneration

Age-related macular degeneration (AMD) is the leading cause of blindness in the United States, impacting millions of older adults. It affects the retina, the thin layer of light-sensitive tissue at the back of the eye. The macula, the central part of the retina, is responsible for our central vision, allowing us to see fine details, drive, and recognize faces. As people age, the macula can deteriorate, leading to AMD.

Currently, there is no cure for AMD; however, retina specialists are continually researching the development of new and effective treatments. Patients can also participate in ongoing clinical trials.

Dry and Wet AMD

There are two types of AMD: dry and wet. The dry form is more common and can affect one or both eyes. Although this condition is usually painless, it leads to changes in vision, such as increased blurriness, visual distortions, and a diminished ability to perceive colors. Dry AMD progresses through three stages: early, intermediate, and late (advanced). Many individuals with AMD may not notice symptoms until the disease reaches the late stage.

In approximately 10% of cases, dry AMD can progress to wet AMD. Wet AMD is more severe than dry AMD and is considered an advanced stage of the disease. It occurs when abnormal blood vessels form in the retina and begin leaking blood or fluid into the macula. For some patients, wet AMD can lead to permanent vision loss.

Geographic Atrophy

Geographic atrophy (GA) is the final stage of dry AMD and typically affects both eyes. It's characterized by atrophic lesions that initially develop in the outer retina and gradually expand to include the macula and the fovea, which is the central part of the macula where vision is sharpest. Vision loss due to geographic atrophy is permanent.

AMD Symptoms

AMD symptoms can vary depending on the stage of the disease. In the early stages, AMD may not produce noticeable symptoms. However, as the condition progresses, patients may experience:

• Blurry vision
• Visual distortions
• Changes in color perception
• Straight lines appearing wavy
• Difficulty reading or seeing fine details

AMD Risk Factors

Age is the primary risk factor for AMD, with the likelihood of developing the condition increasing significantly after the age of 50. Other risk factors include a family history of AMD, smoking, and obesity. Certain health conditions and lifestyle choices, such as high blood pressure, high cholesterol, diabetes, and poor dietary habits, can also increase the risk of developing the disease.

Is AMD Preventable?

AMD isn't always preventable, but there are ways to reduce your risk. Early intervention can make a significant difference in your vision outcomes, so it's important to schedule regular eye exams, especially if you're over the age of 50. Other steps you can take to lower your risk include:

• Eating a well-balanced diet
• Not smoking
• Maintaining healthy blood pressure and cholesterol levels
• Protecting your eyes from UV rays by wearing sunglasses and hats

Diagnosing AMD

During a retinal exam, your doctor will check for the presence of drusen, which are small yellow or white deposits of fatty proteins that accumulate under the retina. While a small number of drusen is usually considered normal, larger quantities may indicate AMD. The size and amount of drusen can help retina specialists determine the stage of the disease. They may also perform additional diagnostic tests such as:

• Eye dilation: During an eye exam, your doctor will use special drops to widen your pupil, allowing for a better examination of the retina.
• Optical coherence tomography (OCT): This non-invasive technique uses infrared light waves to capture detailed images of the retina.
• Fluorescein angiography: In this test, a retina specialist injects colored dye into the bloodstream. This dye travels to the blood vessels in the eye, and a special camera captures images to identify any abnormalities in the retina.
• Indocyanine green angiography: Like fluorescein angiography, this test also involves an intravenous injection of dye. However, the type of dye used in this test absorbs infrared light, making it easier to visualize deeper blood vessels in the retina.
• Amsler grid test: The Amsler grid consists of a square with a grid pattern and a dot in the center, which can help identify problem areas in the field of vision.

Medications and Treatment Options for AMD

While there isn’t currently a cure for AMD, there are treatment options available to help manage disease progression and protect existing vision, such as:

• Anti-vascular endothelial growth factor (anti-VEGF) medications: Anti-VEGF medications are a group of drugs used to inhibit the growth of abnormal blood vessels in the eye in wet AMD. Examples of anti-VEGF medications include Vabysmo, Eylea, Eylea HD, Cimerli, Lucentis, and Pavblu, which are administered via injection directly into the eye.
• Other eye injections: Syfovre and Izervay are intraocular injections that can help calm the immune response, partially preventing retinal cell damage and slowing the progression of geographic atrophy.
• AREDS2 supplements: Consisting of vitamins C and E, lutein, zeaxanthin, zinc, copper, and beta carotene, AREDS2 supplements are recommended for those with intermediate to advanced AMD to slow disease progression.
• Photodynamic therapy: During photodynamic therapy, a retina specialist administers a light-activated medication intravenously and then uses a laser to activate the drug. This process helps seal off abnormal blood vessels. This treatment is only used in certain cases, typically when anti-VEGF treatments are insufficient.
• Regular monitoring: Monitoring dry AMD, which involves regular eye exams and at-home tools such as the Amsler grid, can help detect wet AMD early and enable timely treatment to prevent vision loss.

AMD Prognosis

The prognosis for AMD depends on the type and severity of the condition. Individuals with dry AMD generally experience slow disease progression over many years. Most patients retain some central vision, although it may become blurry. Advanced dry AMD can lead to significant vision loss, but complete blindness is rare.

In contrast, those with wet AMD may experience a rapid progression of the disease if not treated promptly. Early diagnosis and treatment can significantly improve vision outcomes.