Aims: To establish the range of normal distance stereoacuity and evaluate its development in visually normal children by using the Frisby Davis distance stereotest(FD2).
Methods: The distance stereoacuity of visually normal children aged less than 11 years and of adults was measured with FD2 using a standard testing protocol.
Result: This study involved 94 visually normal children aged 36-131 months and 46 visually normal adults aged 20-49 years. The distance stereoacuity of the children aged 36-59 months was 40.61 ± 9.823 (SD) seconds of arc; that of the children aged 60-119 months, 14.18 ± 8.152 (SD) seconds of arc; and that of the adults, 12.50 ± 4.802 (SD) seconds of arc. The FD2 distance stereoacuity of the children aged 36-59 months differed significantly from that of the older subjects (p = 0.000), and the FD2 distance stereoacuity of the children aged more than 59 months did not differ significantly from that of the adults (p = 0.813).
Conclusion: Distance stereoacuity reaches adult levels at approximately 5 years of age. Our data of the age-related normal values could represent a reference frame for the comparison of data obtained for clinical populations.