From: AMD and the alternative complement pathway: genetics and functional implications
 |  | AMD Subtype | |||
---|---|---|---|---|---|
 | Early | Intermediate | Advanced Dry/Geographic Atrophy | Advanced Neovascular/Exudative/Wet | |
Clinical Features | Drusen | Few small (<63 μm) or medium sized (63–124 μm) | Numerous medium (63–124 μm) + at least 1 large (>125 μm) sized | Extensive medium (63–124 μm) + large (>125 μm) sized | Extensive medium (63–124 μm) + large (>125 μm) sized |
Bruch’s membrane | Thickening | Thickening | Thickening | Thickening | |
Retinal pigment epithelium | Pigmentary abnormalities | Pigmentary abnormalities; atrophy excluding fovea | Atrophy including fovea/macula | Detachment | |
Choroid/choriocapillaris | Decreased vascular density | Decreased vascular density | Atrophy | Choroidal neovascularization; hemorrhage; leak fluid | |
Neural retina | None | Photoreceptor thinning above drusen | Photoreceptor cell death | Photoreceptor detachment and cell death | |
Impairment/outcome | Mild visual impairment (blurred vision or decreased contrast sensitivity) or asymptomatic | Mild visual impairment (blurred spots in central vision or decreased contrast sensitivity) or asymptomatic | Blurred central vision; gradual vision loss | Sudden/profound vision loss |