Systematic review and meta-analysis of the negative outcomes of retinopathy of prematurity treated with laser photocoagulation

Introduction: Retinopathy of prematurity is a leading cause of potentially avertable childhood blindness around the world. And laser photocoagulation is currently performed as a gold standard for retinopathy of prematurity treatment, but it may contribute to elevated myopia and decreased visual field. Therefore, the objective of this meta-analysis is to explore the negative impact of laser photocoagulation for retinopathy of prematurity in terms of anatomic outcomes and structural outcomes. Methods: Studies were retrieved through literature searches in PubMed and EMBASE from 1990 to 2017 in English. Case-control studies that reported anatomic and structural changes or significant complications after laser coagulation or cryotherapy for retinopathy of prematurity were eligible. Results: This meta-analysis included eight original studies related to laser treatment for retinopathy of prematurity at any stages. A total of 1422 infants were participated, of which 1156 documented subthreshold or threshold retinopathy of prematurity without laser treatment were selected as comparison group and the rest treated with diode or argon laser coagulation were chosen for experiment group. Taking all included studies into account, spherical equivalent (mean difference -2.53, 95% confidence interval: -5.23 to 0.18, I-2 = 96%, P < 0.00001), anterior chamber depth (mean difference -0.52, 95% confidence interval: -0.76 to -0.28, I-2 = 55%, P = 0.11), astigmatism (odds ratio 3.19, 95% confidence interval: 1.61 to 6.32, I-2 = 0%, P = 0.54), and myopia (odds ratio 8.08, 95% confidence interval: 3.79 to 17.23, I-2 = 37%, P = 0.21) were associated with laser treatment for retinopathy of prematurity. Axial length (mean difference -0.01, 95% confidence interval: -0.28 to 0.27, I-2 = 0%, P = 0.62) and anisometropia (odds ratio 4.21, 95% confidence interval: 0.54 to 33.17, I-2 = 1%, P = 0.31) had no statistical significance on laser coagulation for retinopathy of prematurity. Conclusion: This meta-analysis showed that spherical equivalent, anterior chamber depth, astigmatism, and myopia were associated with the negative outcomes of laser coagulation, while axial length and anisometropia had no statistical importance on the defects of laser coagulation. Therefore, patients treated with laser coagulation should follow periodic cycloplegic refraction and receive early optical correction.