Age-Related Macular Degeneration (AMD): Causes and Treatment

Age-Related Macular Degeneration (AMD): Causes and Treatment

Age-related macular degeneration (AMD) is a progressive disease of the macula — the central, highest-resolution region of the retina responsible for detailed central vision, reading, recognising faces, and driving. AMD can cause serious central vision loss, affecting reading, recognising faces and other detailed tasks.

AMD does not cause complete blindness — peripheral vision is preserved — but the loss of central vision is profoundly disabling. Patients describe not being able to read, recognise faces, or perform fine manual tasks, even while remaining mobile and independent.

The Macula — Why It Matters

The macula occupies the central 5–6 mm of the retina, housing the fovea at its centre — a tiny pit densely packed with cone photoreceptors that enable high-acuity, colour vision. This tiny region is responsible for the central 5–10° of visual field, yet this is the part of the visual field used for virtually all critical tasks.

The macula is supported by the retinal pigment epithelium (RPE) — a monolayer of cells beneath the photoreceptors that recycles visual pigments, supports photoreceptor health, and disposes of metabolic waste by transporting it to the choroid (the vascular layer beneath the RPE).

In AMD, this support system fails — waste accumulates, RPE cells degenerate, and photoreceptors die.

Types of AMD

AMD is classified into early/intermediate and late AMD. Late AMD takes two forms: dry (geographic atrophy) and wet (neovascular AMD).

Early and Intermediate AMD

Drusen — extracellular deposits of lipids, proteins, and debris that accumulate between the RPE and Bruch's membrane (the supporting layer beneath the RPE) — are the hallmark early finding. Visible on fundoscopy and OCT as yellow-white spots beneath the retina.

• Small drusen may occur with ageing.
• The size and extent of drusen and accompanying pigment changes help the specialist assess AMD stage and progression risk.
• A population estimate cannot predict an individual eye's course.

Most patients with early AMD have no or minimal visual symptoms. Some may notice mild difficulty with dark adaptation.

Late Dry AMD — Geographic Atrophy (GA)

In geographic atrophy, patches of RPE and overlying photoreceptors irreversibly degenerate, creating sharply demarcated areas of atrophy that expand slowly until they encroach on the fovea, causing central scotoma (blind spot in central vision).

GA may affect both eyes and progress over time. In the United States, pegcetacoplan (Syfovre) and avacincaptad pegol (Izervay) have FDA approval for GA secondary to AMD. These treatments aim to slow lesion growth; they do not restore tissue already lost. Their schedules and risks are product-specific. US approval does not establish approval, stock or suitability in China.

Late Wet AMD — Neovascular AMD (nAMD)

In neovascular AMD, choroidal neovascularisation (CNV) occurs — abnormal new blood vessels grow from the choroid through Bruch's membrane and beneath or into the RPE, driven by vascular endothelial growth factor (VEGF). These vessels are fragile and leak fluid and blood into and beneath the retina, causing:

• Rapid, often sudden distortion of central vision (metamorphopsia) — straight lines appear wavy or bent
• Central blurring or grey area (scotoma)
• Reduction in reading vision

Wet AMD can progress quickly. New distortion or a new central blind spot needs prompt ophthalmic assessment; treatment should not be delayed while arranging travel.

Risk Factors

Risk factor	What to discuss
Age	AMD becomes more common with increasing age
Smoking	Stopping smoking is an important modifiable step
Family history	Tell the specialist about relatives with AMD
General health	Discuss cardiovascular health and other conditions with your clinician

Diet and supplements: The original AREDS formula contains vitamins C and E, zinc, copper and beta-carotene. AREDS2 replaces beta-carotene with lutein and zeaxanthin. NEI reports about a 25% reduction in progression from intermediate to advanced AMD in the relevant studied groups, not prevention of AMD onset. Current and former smokers should avoid beta-carotene-containing AREDS because of increased lung-cancer risk. Omega-3 supplements did not provide an AMD benefit in these trials. Discuss the appropriate formula and your medicines with your clinician.

Diagnosis

Fundoscopy

Dilated fundoscopy by an ophthalmologist visualises drusen, RPE changes, areas of atrophy, and signs of neovascularisation (subretinal haemorrhage, grey-green CNV membrane beneath the retina).

Optical Coherence Tomography (OCT)

The essential investigation for AMD — provides cross-sectional, high-resolution images of retinal layers:

• Identifies drusen location and size
• Detects subretinal and intraretinal fluid (hallmarks of active wet AMD)
• Measures central retinal thickness and RPE integrity
• Monitors treatment response (fluid resolution with anti-VEGF)

OCT Angiography (OCTA) — non-invasive, dye-free imaging of retinal and choroidal blood flow; identifies CNV networks without fluorescein injection.

Fluorescein Angiography (FFA)

Intravenous fluorescein dye with retinal photography; maps choroidal neovascularisation (classic vs occult CNV), areas of leakage, and guides photodynamic therapy decisions. Less commonly needed since OCT and OCTA advances.

Amsler Grid

A simple home-monitoring tool — a grid of horizontal and vertical lines with a central dot. Patients check daily whether lines appear wavy, distorted, or missing (metamorphopsia) — early warning sign of new wet AMD activation requiring urgent ophthalmology review.

Treatment

Wet AMD — Anti-VEGF Injections

Anti-VEGF therapy has transformed wet AMD from a rapidly blinding condition to one that can be stabilised, with many patients gaining vision. VEGF inhibitors block the neovascular growth signal, cause regression of the abnormal vessels, and reduce fluid leakage.

Treatment selection and monitoring: Anti-VEGF medicines used in retinal care include ranibizumab, aflibercept and faricimab; bevacizumab has also been used off-label in some settings. These examples are not a claim that every product or formulation is authorised or available at a particular Chinese hospital.

The retinal specialist selects the medicine, explains its risks and sets an injection and monitoring plan based on the product, disease activity and response. There is no single loading schedule or longest interval that applies to all patients and formulations. OCT helps monitor retinal fluid and guide follow-up.

An intravitreal injection delivers medicine into the eye using local anaesthesia and infection-prevention procedures. Ask the service about preparation, aftercare and symptoms that need urgent attention. Vision may stabilise or improve, but results vary and repeated treatment may be needed. Do not change the schedule without the treating team.

Dry AMD — Supplements and Emerging Treatments

AREDS2 supplementation may be appropriate for intermediate AMD or particular cases with late AMD in one eye. It does not restore lost vision or replace assessment for wet AMD. Confirm your stage and suitability rather than choosing supplements from a generic list.

Geographic atrophy: the US-approved complement inhibitors described above have separate prescribing information. Ask a retinal specialist about likely benefit, injection-related and drug-related risks, monitoring and local access; this guide does not prescribe a shared interval.

Lifestyle Modifications

• Smoking cessation — the most impactful modifiable intervention
• Mediterranean diet rich in leafy greens, fish, and olive oil
• Daily Amsler grid monitoring to detect wet AMD conversion early
• Protection from UV light (sunglasses)

AMD Care in China

For a proposed visit, ask the receiving retinal service which assessments it offers, such as fundoscopy, visual acuity testing and OCT, and whether further imaging is indicated. Confirm the exact medicine and formulation, local authorisation, availability and follow-up requirements before travel.

Ask for an itemised hospital quotation and a plan for continuing monitoring after you return home. Low-vision rehabilitation, magnification aids and other support may also be relevant. Confirm the provider, language and scope of any coordination separately; this article does not guarantee a drug, appointment, English-speaking clinician or lower cost than another country.

Contact a PriumCare care navigator to arrange a macular assessment, AMD evaluation, or anti-VEGF injection consultation.

Sources and editorial correction

• NEI: AMD overview.
• NEI: AREDS and AREDS2.
• NICE: AMD assessment and treatment.
• FDA: faricimab trial snapshot.
• FDA: Syfovre prescribing information (2024).
• FDA: Izervay trial snapshot.

Editorial source correction: 25 October 2026. This check addressed supplement formulations, treatment-schedule generalisations, unsupported numeric prognosis and comparative marketing claims, and the distinction between US authorisation and local access. It is not a clinical review of the whole article and does not certify an individual treatment plan. No named medical reviewer is claimed. Original publication date is retained.