Overview

AMD is the leading cause of blindness in individuals > 65 years in developed countries.

• Age of onset: usually > 55 years

• Prevalence: 1.47%

• Sex: ♀ > ♂

• Multifactorial

• Risk factors

  • Advanced age

  • Family history and genetic predisposition

  • Cardiovascular disease

  • Smoking

  • Obesity

AMD is characterized by progressive degenerative changes in the central part of the retina (macula) → visual impairment.

• Dry AMD (∼ 90%)

  • Also referred to as nonexudative AMD or atrophic AMD

  • Deposition of yellow-whitish material consisting of lipids, vitronectin, and other proteins (drusen) in the retinal pigment epithelium and between it and Bruch membrane → slow progressive atrophy of the local retinal pigment epithelium (centrally or pericentrally)

• Wet AMD (∼ 10%)

  • Also referred to as exudative AMD or neovascular AMD

  • Choroidal neovascularization (between the retinal pigment epithelium and Bruch's membrane) → leaking of intravascular serous fluid and blood → sudden localized elevation of the macula and/or detachment of the retinal pigment epithelium

• Painless central or pericentral visual impairment → reduced visual acuity, difficulty adapting to changes in lighting

  • Dry AMD: slow progressive visual impairment (usually over decades) and unilateral or bilateral onset

  • Wet AMD: acute or insidious onset (over weeks to months) and usually manifests in one eye first

• Metamorphopsia: type of visual distortion in which straight lines appear wavy, which can be tested for using an Amsler grid

• Scotoma (blind spot)