Macular degeneration

Definition:

• AMD is a common eye condition and a leading cause of vision loss among people age 50 and older. It involves damage to the macula, a small spot near the center of the retina that is needed for sharp, central vision.

Types:

1. Dry AMD (Atrophic):
   • More common and less severe.
   • Characterized by thinning of the macula and formation of drusen (tiny yellowish deposits).
2. Wet AMD (Neovascular or Exudative):
   • Less common but more severe.
   • Characterized by the growth of abnormal blood vessels under the retina, leading to leakage of fluid or blood.

Epidemiology:

• Prevalence increases with age.
• More common in Caucasians and females.

Risk Factors:

• Age (>50 years).
• Family history of AMD.
• Smoking.
• Hypertension, cardiovascular disease.
• Obesity and diet lacking in fruits and vegetables.

Pathophysiology:

• The exact cause is unknown.
• In dry AMD, cellular debris accumulates between the retina and the choroid, and the retina can become detached.
• In wet AMD, abnormal blood vessel growth is stimulated by vascular endothelial growth factor (VEGF).

Clinical Features:

• Gradual loss of central vision.
• Blurred or fuzzy vision.
• Difficulty in reading fine print or recognizing faces.
• Straight lines appear wavy (wet AMD).
• No pain or redness of the eyes.

Diagnosis:

• Comprehensive eye examination.
• Visual acuity test.
• Dilated fundus examination.
• Optical coherence tomography (OCT) to visualize the retina.
• Fluorescein angiography for wet AMD.

Management:

• No cure for dry AMD, but progression can be slowed down with dietary supplements (AREDS2 formula).
• Wet AMD can be treated with anti-VEGF injections, laser therapy, and photodynamic therapy.

Prevention:

• Regular eye exams.
• Smoking cessation.
• Maintaining a healthy diet rich in green, leafy vegetables and fish.
• Controlling other medical conditions like hypertension and obesity.