Related Experiment Video
Updated: Jun 14, 2025
Comparison of Three Clinical Stereoscopic Methods for Measuring Binocular Visual Function During Amblyopic Treatment in Unilateral Amblyopia
Published on: September 27, 2024
The repeatability of accommodative accuracy in childhood unilateral amblyopia
Kristine Huang1, Angela M Chen1, T Rowan Candy2
1Southern California College of Optometry at Marshall B. Ketchum University, Fullerton, California, USA.
Purpose:
Unilateral amblyopia is associated with inaccurate accommodation when viewing monocularly with the amblyopic eye, such as when performing traditional amblyopia therapies. This study investigated the repeatability of the accommodative responses over time to understand the likely pattern of defocus during these therapies.
Methods:
Children with (n = 17) and without (n = 18) unilateral amblyopia between 4 and 15 years of age completed two study visits within 1 week. During each visit, monocular distance and near visual acuity, near stereoacuity, Worth Four Dot testing and ocular alignment were assessed with the habitual optical correction, if worn. Monocular accommodative responses were evaluated three times, separated by 15-min intervals, using modified Nott dynamic retinoscopy while participants viewed broadband naturalistic images at 25, 33 and 50 cm.
Results:
Linear mixed models, with accommodative response and range of values as the dependent variables, showed that accommodative lags increased with stimulus demand, particularly for the amblyopic eyes with the worse visual acuity (p < 0.0001). The range of accommodative responses across repeated measures within a visit was typically less than 0.75 D and was consistent across visits (p > 0.17), with no main effect of visual acuity (p > 0.21).
Conclusion:
These data suggest that the increased retinal defocus experienced by children with amblyopia during monocular viewing for amblyopia therapy is relatively stable. Whether this defocus impacts the success of amblyopia therapy remains an open question.
