Visual acuity, contrast sensitivity, peripheral vision and refraction in low birthweight teenagers

To assess visual acuity (VA), contrast sensitivity, visual fields, refractive errors and use of correction in adolescents with very low birthweight (VLBW; birthweight < 1500 g) and adolescents born at term but small for gestational age (SGA; birthweight < 10th percentile) in a population-based study.

Ophthalmological examination including VA, Vistech contrast sensitivity and Humphrey two-zone, 120-point perimetry was performed in 51 VLBW, 59 SGA and 77 control adolescents.

The VLBW adolescents had reduced VA, reduced contrast sensitivity, and were more often anisometropic compared with control adolescents. They had started wearing glasses earlier, but were not more likely to use correction as teenagers. However, they were more often undercorrected (for refractive status) than control adolescents. Hypermetropia was more common in the SGA group than in the control group, but otherwise the SGA group did not differ from the control group.

Being born SGA may be a risk factor for hypermetropia in adolescence. Prematurely born adolescents present lower VA and contrast sensitivity and are more prone to anisometropia than adolescents born at term. It may be noteworthy that a higher proportion of VLBW than control adolescents were undercorrected, despite the well known vulnerability of visual function associated with preterm birth.