COMPARISON OF TRADITIONAL VISION THERAPY AND HTS2 VISION THERAPY IN YOUNG ADULTS WITH NON STRABISMIC BINOCULAR VISION DYSFUNCTION

Abstract

Purpose: To assess and compare the effect of HTS2 vision therapy with traditional vision therapy in young adults with convergence insufficiency and co-existing accommodative dysfunction.

Methods: In this study, 54 subjects with convergence insufficiency (CI) and co-existing accommodative dysfunction were recruited. 27 Subjects were assigned to traditional vision therapy (VT) and 27 subjects were assigned to HTS2 vision therapy for 4 days per week for a period of one month. After one month of therapy, vergence parameters such as near exophoria, near point of convergence (NPC), near positive fusional vergence (PFV), vergence facility (VF) and accommodative parameters such as amplitude of accommodation (AA), negative relative accommodation (NRA), positive relative accommodation (PRA), monocular accommodative facility (MAF), accommodative response (MEM) and convergence insufficiency symptom survey questionnaire (CISS) scores were assessed. Data analysis was performed with Mann Whitney U Test and Wilcoxon Sign Rank Test.

Results: After one month of therapy, any statistically significant difference was not found in the mean values of vergence, accommodative parameters and CISS scores between traditional VT group and HTS2 VT group (p > 0.05). However, in both the groups a significant improvement was observed in near phoria, vergence, accommodative parameters and CISS scores of the subjects underwent VT (p < 0.05).

Conclusion: HTS2 VT is also found to be an effective treatment for improving vergence, accommodative function and reducing symptoms in the patients with CI and co-existing accommodative dysfunction and may be used as an alternative treatment to more time consuming, expensive traditional VT which is office-based for those who cannot visit the office.

Keywords: Convergence insufficiency, accommodative dysfunction, office-based vision therapy, HTS2