Age-Related Macular Degeneration (AMD)

Age-Related Macular Degeneration (AMD) is a progressive eye disease and the leading cause of central vision loss in people over 50. It affects the macula, the part of the retina responsible for sharp, central vision needed for reading, driving, and recognizing faces.



Types of AMD

1. Dry (Atrophic) AMD (90% of cases)

  • Cause: Gradual breakdown of light-sensitive cells (photoreceptors) and drusen (yellow deposits under the retina).


  • Symptoms:

    • Blurred central vision

    • Difficulty recognizing faces

    • Need for brighter light when reading


  • Progression: Slow, but can advance to geographic atrophy (severe thinning of retinal layers).


  • Treatment:

    • 1.No cure, but AREDS2 supplements (vitamins C, E, zinc, copper, lutein, zeaxanthin) may slow progression.

    • Lifestyle changes (quit smoking, UV protection, healthy diet rich in leafy greens).


2. Wet (Neovascular/Exudative) AMD (10% of cases, more severe)

  • Cause: Abnormal blood vessels grow under the retina (choroidal neovascularization), leaking blood/fluid, causing rapid vision loss.



  • Symptoms:

    • Sudden distortion (e.g., straight lines appear wavy – Amsler grid test)

    • Dark/blurry spots in central vision

    • Rapid vision decline


  • Treatment:

    • Anti-VEGF injections (e.g., Lucentis, Eylea, Avastin, Vabysmo) to block abnormal blood vessel growth.


    • Photodynamic therapy (PDT) (less common now).

Risk Factors

✅ Age (most common in >60 years)
✅ Genetics (family history, genes like CFH, ARMS2)
✅ Smoking (doubles risk)
✅ Race (more common in Caucasians)
✅ Cardiovascular disease & hypertension
✅ Obesity & poor diet (low in antioxidants)
✅ Prolonged UV exposure


Diagnosis

  1. Comprehensive Eye Exam (dilated fundus exam).

  2. Amsler Grid Test (checks for distortion).

  3. Optical Coherence Tomography (OCT) – Detailed cross-section of retina.

  4. Fluorescein Angiography – Detects leaking blood vessels (for wet AMD).

Prevention & Management

✔ AREDS2 Supplements (for intermediate/advanced dry AMD).
✔ Quit smoking (major modifiable risk).
✔ Healthy Diet (leafy greens, fish high in omega-3).
✔ UV-protective sunglasses.
✔ Regular eye exams (especially if >50 or family history).


Emerging Treatments (Research Stage)

  • Stem cell therapy (retinal cell regeneration).

  • Gene therapy (targeting genetic causes).

  • Complement inhibitors (for geographic atrophy).

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