Full extent of the contour interaction area. Figure 2 presents the results of three studies that have measured the full contour interaction area in children and adults with NV. Differences between the studies can partially be explained by the different optotypes used. The study by Semenov used Landolt C’s with flanking bars and the study by Jeon et al used E-gratings surrounded by gratings. E-gratings are more difficult to identify than C-rings for children, which might explain the larger contour interaction areas when E-gratings are used [20,23]. Error bars ± 1 s.e.m.
Huurneman et al. BMC Ophthalmology 2012 12:27 doi:10.1186/1471-2415-12-27