Stage 4 ROP is associated with which finding?

• A. Total retinal detachment
• B. Neovascularization extending into the vitreous
• C. Retinal edema
• D. Vascularization limited to the optic disc

Answer: (B)

Stage 4 ROP reflects a partial retinal detachment caused by traction from fibrovascular tissue that has developed from abnormal retinal vascularization. This is different fromStage 3, which features extraretinal neovascularization extending into the vitreous. Total retinal detachment is seen in the more advanced stage 5, and vascularization limited to the optic disc or retinal edema are not defining features of stage 4. So the finding described as neovascularization extending into the vitreous belongs to stage 3, not stage 4.