Forty eyes in twenty-two cases in the active phase of retinopathy of prematurity were treated with laser photocoagulation.
Thirty (93.7%) of the 32 eyes in type I and intermediate type were found in the cicatrical phase grade 1. In type II in which cryocautery was used as combination therapy, only 2 eyes (25.0%) were found in grade 1, 2 eyes (25.0%) in grade 2, 1 eye (12.5%) in grade 4 and 3 eyes (37.5%) in grade 5.
All 21 eyes in which photocoagulation was performed up to the middle of stage 3 were found in grade 1 (100%). However, among 11 eyes in which photocoagulation were performed in late stage 3, 9 eyes (81.8%) were found in grade 1, and 2 eyes (18.2%) in grade 2.
In conclusion, if adequate laser photocoagulation is performed in avascular areas at the middle of stage 3 of type I and intermediate type, treatment in cicatrical phase grade 1 is possible. Laser photocoagulation is clearly more effective than the xenon arc photocoagulation or cryocautery. However, in type II it is difficult to control the condition by photocoagulation alone, and early diagnosis followed by combination therapy using cryocautery is required.