Macular Degeneration (Age-Related Macular Degeneration)

What the macula does

The retina lines the back of the eye like the film in a camera. The macula, about 5 mm across, is packed with cone cells that give fine detail and color vision. You use it for reading, driving, recognizing faces and threading a needle. In AMD, waste deposits, inflammation and blood vessel changes damage the macula and the support layer beneath it (the retinal pigment epithelium).

Types and stages

Dry AMD

• Early AMD: medium-sized yellow deposits (drusen) under the retina; usually no symptoms.
• Intermediate AMD: large drusen and pigment changes; some blur or need for more light.
• Late dry AMD (geographic atrophy): patches of retinal cells die, creating blind spots in central vision. Progression is slow, over years.

Wet (neovascular) AMD

Abnormal blood vessels grow from beneath the retina (choroidal neovascularization) and leak fluid or blood, causing rapid distortion and vision loss. Wet AMD accounts for only about 10 to 20% of AMD but most severe vision loss. Any stage of dry AMD can convert to wet AMD.

Symptoms

• blurred or reduced central vision
• straight lines looking wavy or bent (metamorphopsia), see distorted vision
• a dark, gray or blank spot in the center of vision
• difficulty reading or seeing fine detail
• trouble recognizing faces
• needing brighter light; slow adjustment from bright to dim light
• colors looking less vivid

AMD does not cause total blindness, because peripheral vision is spared. Some people with significant vision loss experience visual hallucinations called Charles Bonnet syndrome, which are harmless and not a sign of mental illness.

Risk factors

• Age: the biggest risk factor; most common after 60
• Smoking: roughly doubles to triples the risk
• Family history and genetics (CFH and ARMS2 genes)
• White race (higher rates)
• high blood pressure, heart disease, high cholesterol and obesity
• diet low in leafy greens and fish

Diagnosis

• Visual acuity test and Amsler grid
• Dilated eye exam to see drusen, pigment changes, bleeding or atrophy
• Optical coherence tomography (OCT): a fast, non-invasive scan showing retinal layers, fluid and atrophy; used at most follow-up visits
• Fluorescein or indocyanine green angiography and OCT angiography to detect abnormal vessels in wet AMD
• Fundus autofluorescence to measure geographic atrophy

Conditions that can look similar include central serous chorioretinopathy, diabetic macular edema, macular hole and epiretinal membrane.

Treatment

AREDS2 supplements

The Age-Related Eye Disease Studies (AREDS and AREDS2) found that a specific formula reduces the risk of progression to late AMD by about 25% in people with intermediate AMD or late AMD in one eye. The AREDS2 formula contains vitamin C, vitamin E, zinc, copper, lutein and zeaxanthin. It does not help people without AMD or with only early AMD. The original formula contained beta-carotene, which raises lung cancer risk in smokers; AREDS2 replaces it with lutein and zeaxanthin.

Anti-VEGF injections for wet AMD

Medicines that block vascular endothelial growth factor (VEGF), such as aflibercept, ranibizumab, bevacizumab and faricimab, are injected into the eye after numbing drops. They stop vessel leakage and growth, stabilize vision in most people and improve it in many. Injections usually start monthly and are then spaced out ("treat and extend") based on OCT results. Long-term treatment is usually needed. Early treatment gives the best results.

Treatment for geographic atrophy

Two complement inhibitors, pegcetacoplan and avacincaptad pegol, given as regular eye injections, can slow the growth of geographic atrophy. They do not restore lost vision, and they carry risks including converting to wet AMD, so decisions are individualized.

Other options

Photodynamic therapy is used occasionally for certain forms of wet AMD. Laser photocoagulation is now rarely used.

Living with macular degeneration

• Low-vision services: magnifiers, bright task lighting, large-print and audio books, high-contrast settings, screen readers and smartphone accessibility tools. See low vision.
• Home Amsler grid checks daily or weekly for each eye separately.
• Driving: follow your eye doctor's advice and local vision standards.
• Support groups and occupational therapy for daily tasks.
• Regular eye exams as scheduled.

Prevention and lowering risk

• Do not smoke, and quit if you do.
• Eat leafy green vegetables (spinach, kale), colorful fruit and vegetables, and fish twice a week.
• Exercise and maintain a healthy weight.
• Control blood pressure and cholesterol.
• Wear sunglasses that block UV light.
• Have dilated eye exams, especially with a family history.

Frequently asked questions

What are the first signs of macular degeneration?

Early AMD often has no symptoms. The first signs are usually difficulty reading in dim light, blurry central vision, needing more light, and straight lines looking slightly wavy. A sudden increase in distortion or a dark spot may mean wet AMD and needs prompt evaluation.

What is the difference between wet and dry macular degeneration?

Dry AMD is more common and progresses slowly through drusen deposits and thinning of the macula. Wet AMD occurs when abnormal blood vessels grow and leak under the retina, causing faster vision loss. Wet AMD is treated with eye injections.

Can macular degeneration be cured?

There is no cure, but treatment can slow or stop vision loss. Anti-VEGF injections often stabilize and sometimes improve vision in wet AMD. AREDS2 supplements slow progression of intermediate dry AMD, and newer injections slow geographic atrophy.

Do eye vitamins help macular degeneration?

The AREDS2 formula reduces the risk of advanced AMD by about 25% in people with intermediate AMD or advanced AMD in one eye. It does not prevent AMD in people who do not have it or help early AMD. Ask your eye doctor whether it is right for you.

Does macular degeneration cause blindness?

AMD can cause severe loss of central vision, making reading and recognizing faces difficult, and some people meet the definition of legal blindness. However, it does not usually cause complete blindness, because side vision is preserved.