Refractive errors in infants with retinopathy of prematurity treated using laser or anti-vascular endothelial growth factor monotherapy

Abstract Background: Infants treated for retinopathy of prematurity (ROP) could develop visually significant refractive errors. In this study, we report pre-treatment refractive errors in premature infants with treatment-requiring ROP treated using laser or anti-VEGF monotherapy and compare the components of post-treatment refractive error values between the two treatment groups at different follow-up timepoints. Methods: In this retrospective cohort study, we analyzed ۳۶۰ eyes of ۱۸۱ premature infants with treatment-requiring ROP who were referred to Farabi Eye Hospital, Tehran, Iran between March ۲۰۲۰ and April ۲۰۲۱. Of the ۳۶۰ eyes, ۱۹۵ received laser monotherapy (laser treatment group) and ۱۶۵ received an intravitreal anti-VEGF injection (anti-VEGF therapy group). All included eyes underwent pre- and post-treatment cycloplegic refraction. Cycloplegia was induced for each infant by instilling a mixed eye drop containing ۱% tropicamide, ۲.۵% phenylephrine, and ۰.۵% tetracaine (in equal volumes) in each eye three times at five-minute intervals. Cycloplegic refraction was performed ۳۰ minutes after the third instillation. Results: The mean (standard deviation [SD]) gestational age (GA) and birth weight (BW) of the infants were ۲۹.۰ (۲.۰) weeks and ۱۲۴۱.۰ (۴۰۳.۰) g, respectively. The male-to-female ratio in the entire study cohort was ۱۰۷ (۵۹.۱%) / ۷۴ (۴۰.۹%), whereas the ratios in the anti-VEGF therapy group and laser treatment group were ۴۷ (۵۶.۶%) / ۳۶ (۴۳.۴%) and ۶۰ (۶۱.۲%) / ۳۸ (۳۸.۸%), respectively. The pre-treatment assessment revealed that ۲۱۸ (۶۰.۶%) eyes were hyperopic, ۱۱۲ (۳۱.۱%) were myopic, and ۳۰ (۸.۳%) were emmetropic. In the anti-VEGF therapy group, ۸۷ (۵۲.۷%) eyes were hyperopic, ۶۳ (۳۸.۲%) were myopic, and ۱۵ (۹.۱%) were emmetropic. In the laser treatment group, ۱۳۱ (۶۷.۲%) eyes were hyperopic, ۴۹ (۲۵.۱%) were myopic, and ۱۵ (۷.۷%) were emmetropic. The mean (SD) spherical refractive error and spherical equivalent of refractive error (SEQ) at the ۱-week, ۱-month, and > ۶-month post-treatment follow-up timepoints; the mean cylindrical refractive error at the ۳-month post-treatment timepoint; and the mean SEQ at the time of ROP regression were significantly different between the treatment groups (all P < ۰.۰۵). The rate of anisometropia increased significantly from ۳.۴% at baseline to ۹.۲% at the ۶-month post-treatment follow-up timepoint (P < ۰.۰۵). Conclusions: In this study, the most common pre-treatment refractive status of all included eyes with treatment-requiring ROP and eyes in each treatment group was hyperopia, followed by myopia and emmetropia. At the more than ۶-month post-treatment follow-up, cycloplegic refraction revealed that the laser-treated eyes were significantly more hyperopic than the anti-VEGF-treated eyes, a finding similar to the pre-treatment refraction results. Further studies of same cohort with a longer follow-up period and a control group are needed to determine the real-world effect of each treatment modality on the refractive statuses of children treated for ROP. Keywords: infants neonate premature infant prematurity retinopathy refractive error laser therapies intravitreal injection VEGFs Avastin