Visual Contrast Functions in Children with Severe Visual Impairment and the Relation to Functional Ability

The purpose of this study was to evaluate the contrast sensitivity of children with severe visual impairment and to correlate these findings with the children's performance in five areas of functional capability. Twenty children, 6–16 years of age, with severe visual impairment were included in the study. The children were divided into two groups: Group I (n = 9, all with visual deprivation) and Group II (n = 11, with retinal-related diseases). The children were assessed with six different high- and low-contrast visual acuity tests. Functional vision was assessed with regard to communication, orientation, mobility, ADL (activities of daily living) and sustained near-vision tasks. The performances were graded on a scale of 1–5 in the five different areas. High-contrast distance visual acuity tests were generally not well correlated amongst themselves in either group, whereas near-vision and low-contrast tests were well correlated in Group I but not in Group II. The low-contrast tests were well correlated a...