Critical mass retinopathy of prematurity: what is it and what can you do about it?

This paper presents a summary of my experience with treatment of 41 patients with retinopathy of prematurity. From November, 1976, to June, 1988, 76 eyes with Stage 3b, 3c, and Stage 4 ROP had treatment to the ridge-EFP complex, the avascular retina, or both locations. Cryotherapy was used in all eyes, with two having Argon laser photocoagulation as well. These studies have shown that: 7.9% of all treated eyes had Grade III to V RLF; the optimal timing of intervention is recommended during progression of Stage 3b+ ROP; the optimal location of treatment appears to be the avascular retina with the ridge-EFP perhaps as effective but the treatment of both areas simultaneously is to be avoided due to an increased occurrence of grade II RLF and macular pigment epitheliopathy in those eyes so treated. A comparison of results of four major studies indicate that the U.S. Cryo-ROP Study has three times the rate of Grade III to V RLF, probably because of intervention after the accumulation of excessive quantities of Stage 3b and/or 3c ROP.