1. Flat demarcation line separating the vascular from the avascular peripheral
retina.
2. The demarcation line is ridged/elevated.
3. Fibrovascular proliferation or neovascularization along the demarcation
line.
4. Partial retinal detachment, further defined by Stage 4A and Stage 4B:
a. Macula on
b. Macula off
5. Total retinal detachment.
· Plus Disease: Any ROP with at least two quadrants of engorged/tortuous
vasculature.