Characteristics of binocular vision and oculomotor function among sports-concussed athletes

Abstract

Purpose: To compare the binocular vision and oculomotor function between sports-concussed athletes and aged-matched controls. Methods: Thirty mild concussed athletes were recruited and compared with aged-matched controls. All the participants underwent a comprehensive ocular assessment followed by an oculomotor assessment which included tests for accommodation, vergence, eye movements, and reading parameters. Results: Three categories of oculomotor-based deficits were found: convergence insufficiency (40%), accommodative insufficiency (25%), and oculomotor-based reading dysfunctions (20%). A statistically significant reduction in the mean ± SD of the following parameters was noted in concussed athletes v/s controls:- binocular accommodative amplitude: 7.13 ± 1.59 v/s 15.35 ± 2.95 (P < 0.001), convergence amplitude: 14.23 ± 5.00 v/s 5.65 ± 0.90 (P < 0.001), positive fusional vergence for distance: 21.17 ± 8.97 v/s 31.32 ± 6.23 (P < 0.001), vergence facility: 6.47 ± 1.47 v/s 11.84 ± 1.00 (P < 0.001), accommodative facility: 7.10 ± 4.57 v/s 11.67 ± 1.83 (P < 0.001), reading speed: 66.97 ± 17.82 v/s 144.13 ± 24.45 (P = 0.03) and Developmental Eye Movement ratio: 1.40 ± 0.19 v/s 1.17 ± 0.06 (P < 0.001). Conclusion: Concussions caused by sports have a considerable impact on binocular vision and oculomotor parameters. These findings have substantial therapeutic implications in terms of establishing a periodic screening program for athletes so that essential therapy can be provided for a better outcome.