Crowding ratios measured with charts with 50% interoptotype spacing. Figure 5 presents the results of four studies which have measured crowding ratios in children and adults with normal vision (NV) and children with cerebral visual impairment (CVI). Line means that the crowding ratio was calculated by dividing the single through the line acuity score and circular means that the crowding ratio was calculated by dividing the single acuity through the acuity score that was measured when a target symbol was surrounded by 6 symbols surrounding the target in all directions. A clear age related reduction of the crowding ratio was observed in children with NV. Error bars ± 1 s.e.m.
Huurneman et al. BMC Ophthalmology 2012 12:27 doi:10.1186/1471-2415-12-27