Pathology and Pathogenesis of Retinal Vasculitis

Vascular Occlusion and Ischemia

• The retina has dual blood supply: inner layers from retinal arteries, outer layers from choroidal vessels, and when hypoperfusion occurs, ischemia predominantly affects the inner retinal layers 1
• Experimental data shows retinal arteries can tolerate occlusion up to 97 minutes without damage, but severe irreversible damage occurs after 240 minutes 1

Critical Clinical Distinctions

• In patients over 50, Giant Cell Arteritis (GCA) represents the most common non-embolic cause and constitutes an ophthalmologic emergency, causing inflammatory disease of the proximal ocular artery with vessel wall thickening and occlusion, resulting in simultaneous ischemia of inner and outer retina plus optic disc 1, 3
• Immediate high-dose corticosteroid treatment is critical to prevent vision loss in the fellow eye 1, 3

Systemic Disease Associations

• Behçet's disease shows strong association with posterior segment involvement requiring azathioprine and systemic corticosteroids, and the primary pathology in Behçet's-associated thrombosis is vessel wall inflammation, not thrombophilia 4

Neovascular Complications

• Neovascular glaucoma can develop from new vessels growing on iris and anterior chamber angle structures 2