Refractive Status And Optical Components Of Premature Babies With Or Without Retinopathy Of Prematurity At 3-4 Years Old

Objective:This study aimed to investigate the refractive status and optical components of premature babies with or without retinopathy of prematurity (ROP) at 3-4 years old and to explore the influence of prematurity and ROP on the refractive status and optical components.Methods:From January 2009 t0 February 2011, premature babies receiving fundus photographic screening (FPS) in the Children’s Hospital of Chongqing Medical University were recruited and divided into ROP group and Premature group. Full-term babies matched in age were recruited as controls. Auto-refractomer was employed to detect the corneal refractive power, corneal radius of curvature and corneal astigmatism, A-scan ultrasonography was performed to detect the anterior chamber depth, lens thickness, Vitreous thickness and ocular axial length, and retinoscopy was performed following cycloplegia with 1% cyclopentolate in these babies at 3-4 years old. Incidences of myopia, hyperopia and astigmatism were compared with chi-square test The means of continuous variables were compared with analysis of variance among 3 groups, Pearson correlation coefficient was calculated to evaluate the correlations of birth weight and gestational age with refractive status and optical components., and the correlations of gestational age and birth weight with the refractive status and optical components were evaluated.Results:1. Of 132 subjects, a total of 261 eyes were evaluated in this study, including 59 eyes of 31 subjects in ROP group,118 eyes of 59 subjects in Premature group and 84 eyes of 42 subjects in controls.2. The incidence of corneal astigmatism (-1.35 DC,-1.27 DC,-1.07DC, P<0.05) and the mean degree of astigmatism (0.89DC,0.77DC,0.55DC, P<0.05) in ROP group and Premature group were significantly higher than those in controls. The corneal refractive power in ROP group and Premature group was more potent as compared to controls (43.34D,43.87D, 43.25D, P<0.05); corneal curvature in ROP group and Premature group was significantly lower than that in controls (7.78 mm,7.70 mm and 7.81 mm, P<0.05); lens thickness in ROP group and Premature group was markedly thicker than that in controls (4.37mm,4.36mm,4.47mm, P<0. 05); the ocular axial length in ROP group and Premature group was significantly shorter than that in controls (21.78 mm,21.86 mm and 22.12 mm, P<0.05).3. The gestational age was negatively related to corneal astigmatism (r=-0.182, p=0.003) and astigmatism (r=-0.207, P=0.001), but positively associated with vitreous thickness (r=0.138, P=0.026) and ocular axial length (r=0.181, P=0.003). The birth weight was negatively associated with corneal astigmatism (r=-0.210, P=0.001), astigmatism (r=-0.216, p<0.001) and corneal refractive power (r=-0.226, P<0.001), but positively related to Corneal radius of curvature (r=0.225, P<0.001), vitreous thickness (r=0.233, P<0.001) and ocular axial length (r=0.277, P<0.001).Conclusion:1. Premature babies with or without ROP at 3-4years old are susceptible to myopia and astigmatism.2. ROP, prematurity and low birth weight synergistically influence corneal refractive power、corneal curvature、lens thickness and ocular axial length leading to the development of refractive status.3.Prematurity and low birth weight are more important than ROP in the development of refractive status and optical components.