Purpose: To investigate the refractive status and visual acuity of 3-year-old children with extremely low birth weight (ELBW).
Study design: Retrospective cohort study.
Methods: We examined 161 children born between January 2009 and December 2014. The children were divided into five groups for evaluation of visual acuity and refraction: no retinopathy of prematurity (ROP), reverse ROP, photocoagulation (PC) zone II (ZII), PC (ZI), and PC (ZI + lens-sparing vitrectomy [vit]).
Results: Median (1st quartile, 3rd quartile) gestational age was 25 (24, 26) weeks. Median birth weight was 738 (588, 846) g. Spherical equivalence (SE) was +0.38 (-0.06, +0.75) diopters (D) in no ROP, +0.63 (-0.25, +1.34) D in reverse ROP, +0.38 (-0.75, +1.31) D in PC (ZII), -3.31 (-8.06, +0.16) D in PC (ZI), and -12.00 (-13.50, -4.50) D in PC (ZI+ vit) children. Best corrected visual acuity (BCVA) in log MAR was 0.15 (0.07, 0.26) in no ROP, 0.17 (0.10, 0.30) in reverse ROP, 0.22 (0.10, 0.38) in PC (ZII), 0.45 (0.22, 0.55) in PC (ZI), and 1.10 (0.82, 1.30) in PC (ZI+ vit) children. There was a significant correlation between SE and BCVA (r = -0.43, p < 0.0001).
Conclusion: The no ROP, reverse ROP, and PC (ZII) groups showed no significant differences in SE or BCVA, accounting for 79.5% of ELBW children. SE and BCVA in the PC (ZI) and PC (ZI+ vit) groups were worse than in the other groups. The current results reveal a correlation between SE and BCVA.
Keywords: Extremely low birth weight infant; Refraction; Retinopathy of prematurity; Visual acuity.