AIM: To explore the clinical effect of laser photocoagulation combined with minimal doses of intravitreal ranibizumab(IVR)for aggressive posterior retinopathy of prematurity(AP-ROP).

METHODS: Medical records of 36 eyes of 18 premature infants with a primary diagnosis of AP-ROP were reviewed and analyzed retrospectively. All the lesions were located in posterior zone, with 22 eyes in zone 1 and 14 eyes in zone 2. Six eyes had iris rubeosis, while 8 eyes combined with vitreous hemorrhage. All participants were divided into injection group(0.4mg)or combined group(0.25mg)randomly. Laser photocoagulation was applied on the avascular retina, sparing two-disc diameter width temporal avascular area anterior to ridge in the combined group, meanwhile, a minimal dose(0.25mg)of IVR was conducted. Follow-up ranged from 12-24mo, with a mean of 18.7±6.3mo. The anatomical results and complications were recorded after treatment.

RESULTS: AP-ROP regressed after single therapy in two groups. No infants had localized proliferation or detachment post total treatment. The regression time of neovascular ridges and plus-diseases were 2.01±0.32 and 1.92±0.51wk respectively in injection group, and both were 1.75±0.29wk in combined group. The differences between those two groups were statistically significant(t=3.32, 4.16; P<0.05). The regression time of rubeosis was 1.59±0.07wk in injection group, 1.34±0.18wk in combined group. The differences between those two groups were statistically significant(P<0.05).

CONCLUSION: The combination of laser photocoagulation and intravitreal injection of minimal dosage of ranibizumab is safe and effective in the treatment of AP-ROP.