Application of the binocular phase combination paradigm in quantifying interocular suppression in amblyopia

Abstract

Objective To evaluate the application of the binocular phase combination paradigm in quantifying interocular suppression in amblyopia, and to further assess the correlation between interocular suppression and visual deficits in amblyopia. Methods This was a cross-sectional study. Twenty-five normal controls and 51 patients with monocular amblyopia who had no prior treatment were included in this study. A binocular phase combination paradigm was used to examine an individual's balance point when the two eyes were equally effective. The correlation between balance points and visual deficits, including the visual acuity of the amblyopic eye, stereoacuity and the degree of anisometropia were studied. Results The average balance point of the amblyopic group was 0.227±0.016, far lower than that in normal subjects (0.984±0.020), and the difference was statistically significant (t=27.316, P 0.05). Conclusion A binocular phase combination paradigm can provide a quantitative measure of the binocular status of amblyopia, which is useful in clinical binocular examinations. Key words: Amblyopia; Interocular suppression; Binocular phase combination; Balance point