Table 1. Key clinical features distinguishing different etiologies of infectious chorioretinitis.

	Location	Confluence	Border	Thickness	Vasculitis
Acute retinal necrosis24	Peripheral Multifocal or posterior25	Confluent, Rapid centripetal spread	Smooth with large satellites	Necrotizing Full thickness, opaque, edematous	Occlusion in and outside lesions
Cytomegalovirus	Random Vasocentric	Unifocal or multifocal, Central healing, usually concentric spread	Granular small satellites	Necrotizing, Superficial	Occlusion in lesions FBA reported26
Syphilis	Random Posterior polar predominance	Diffuse	Poorly defined	Non-necrotizing, Translucent, edematous	Vascular leakage Venous occlusion22
Toxoplasmosis, focal	Random	Unifocal with border healing	Smooth	Thick, inner retina or full thickness	Arteriolar >venular sheathing, FBA reported
Toxoplasmosis, diffuse27, 28	Random	Confluent, random spread	Smooth	Usually thick	Arteriolar >venular sheathing

FBA, frosted branch angiitis: heavy deposits of inflammatory material along multiple arteriolar and venular branches.