Evaluation of Ocular Biometric and Optical Coherence Tomography Parameters in Preterm Children Without Retinopathy of Prematurity

PURPOSE: To evaluate and compare biometric and optical coherence tomography parameters of ocular structures in preterm children without retinopathy of prematurity with term children. METHODS: A cross-sectional, comparative study was carried out from 2018 to 2019. In this study, 124 eyes of 62 preterm children were compared with 132 eyes of 66 term children aged between 7 and 9 years. Preterm children were born at 28 to 32 weeks with a birth weight of less than 2 kg with no ocular abnormalities, and term children were delivered at 37 or greater weeks and had a birth weight of 2 kg or more. All children had standardized eye examinations, and ocular measurements using the anterior and posterior segment optical coherence tomography and laser interferometry. RESULTS: Significant differences were found between the term and preterm children for horizontal corneal diameter: median, 12.2 mm (interquartile range [IQR], 0.4) versus median, 12.1 mm (IQR, 0.6; P < 0.005); axial length median, 23.03 mm (IQR, 1.10 mm) versus median, 22.88 mm (IQR, 1.35 mm; P = 0.017); global retinal nerve fiber layer thickness: mean ± standard deviation, 106.54 ± 10.23 µm versus mean ± standard deviation, 103.65 ± 10.178 µm (P = 0.024); temporal retinal nerve fiber layer thickness: median, 76 µm (IQR, 16 µm) vs median, 74 µm (IQR, 14 µm; P = 0.012); and the angle opening distance at 750 µm nasal: mean ± standard deviation, 0.815 ± 0.23 mm vs mean ± standard deviation, 0.749 ± 0.21 mm (P = 0.016). No significant differences were found for other anterior segment and angle parameters. CONCLUSIONS: Preterm children with no retinopathy of prematurity have smaller eyes and thinner retinal nerve fiber layers than their term counterparts. The long-term effects of interrupted ocular growth in preterm children should be further studied into adulthood. TRANSLATIONAL RELEVANCE: Preterm children maybe more predisposed to certain eye conditions because they have smaller eyes, and thus should be further monitored clinically.