A Growing Change in Paediatric Ocular Biometry

Study could offer new basis for monitoring refractive error development in children. Roibeárd O’hÉineacháin reports. Eyes appear to mature differently in boys and girls, according to a study by Franziska G Rauscher PhD and associates that won first prize in the 39th ESCRS Congress poster competition in Amsterdam, the Netherlands. “These data may serve as normative values for assessing eye growth in central European children and will provide a basis for monitoring refractive error development,” the study’s authors noted. The study involved 1,907 children aged 4 to 17 years examined as part of the LIFE Child Study (Leipzig Research Centre for Civilization Diseases), a population-based study in Leipzig, Germany. The children participating in the study underwent optical biometry of their right eyes with the LENSTARR LS 900 (Haag- Streit) to determine axial length, central corneal thickness, flat and steep corneal radii, aqueous depth, lens thickness, and vitreous depth. Girls presented with 0.63 mm shorter eyes than boys at four years of age. However, in this cross-sectional data set, girls’ eyes elongated at a similar rate to boys, reaching the same axial length about four years after the boys. The study’s authors noted in the girls, axial length increased from 21.6 mm at four years old to 23.4 mm by 17 years. The yearly increase was statistically significant up to age 14 (0.174 mm per year). In the boys, axial length increased from 22.2 mm at four years to 23.9 mm at 17 years, but the yearly increase (0.178 mm per year) was statistically significant only up to age 10. Lens thickness decreased in girls from 3.75 mm at four years to 3.47 mm at 10 years with no further statistically significant change between 10 and 17 years. Lens thickness decreased in boys from 3.73 mm at four years to 3.44 mm at 10 years. Lenses reached their minimum thickness at 11 years in girls and 12 years in boys. Central corneal thickness (CCT) in girls did not change statistically significantly between four and seven years of age but increased significantly between seven and 10 years of age with no significant increase thereon. In boys, the CCT did not change statistically significantly between four and 17 years. The overall mean CCT was 550 μm in girls and 554 μm in boys. In girls, corneal curvature was somewhat flatter at age four compared to age 10, whereas it remained constant in boys. Aqueous and vitreous depths increased at the same rate in boys and girls. At age 17, aqueous depth was 3.06 mm for girls and 3.20 mm for boys, and vitreous depth was 16.29 mm in girls and 16.62 mm in boys. The aqueous depth increase matched the lens thickness decrease from four to 10 years of age. All dimensions of the optical ocular components closely correlated with axial length. Dr Rauscher and her associates published their findings in the May 2021 issue of Ophthalmic and Physiological Optics.i iRauscher et al, Ophthalmic Physiological Optics. 2021; 41(3): 496–511. Franziska Rauscher PhD is a Vision Scientist at the Institute for Medical Informatics, Statistics, and Epidemiology (IMISE), Leipzig University, Germany. franziska.rauscher@medizin.uni-leipzig.de