Table 1.

Criteria for retinal vascular pathology scores in retinal whole mounts in oxygen-induced retinopathy

	Score
Criteria	0	1	2	3	4
Central—peripheral avascular areas	None or <50% of zone A	<25% of zones A + B	25–50% of zones A + B	>50% of zones A + B	—
Blood vessel tufts	None	In <3 clock hr	In 3–5 clock hr	In 6–8 clock hr	In 9–12 clock hr
Clusters (presumed extra-retinal neovascularization)	None	In <3 clock hr	In 3–6 clock hr	In >6 clock hr	—
Blood vessel tortuosity	None	<1/3 of vessels	1/3–2/3 of vessels	>2/3 of vessels	—