Changes in Objective Measurements of Divergence Following Vision Therapy For Esophoria

Title Changes in Objective Measurements of Divergence Following Vision Therapy For Esophoria
Author, Co-Author Erin Jenewein, Mitchell Scheiman, Tara Alvarez
Topic Binocular Vision/Pediatrics
Program Number
Ballroom A-B
Pennsylvania College of Optometry at Salus University

Introduction: Previously, clinical testing has been the only method used to demonstrate improvement in vergence function following vision therapy as a treatment for binocular vision disorders. Objective eye movement testing provides an objective assessment of changes in vergence abilities after treatment, and minimizes both subject and examiner bias. Although previous studies have demonstrated objective changes in peak velocity for convergence in patients with convergence insufficiency, we are unaware of any similar reports with esophoria and divergence measures. This case report is the first demonstrating changes in divergence following vision therapy for esophoria.

Case Report: A 25-year-old female presented with complaints of blur, double vision and asthenopia with near work. Initial examination revealed an esophoria of 12Δ at distance and 14Δ at near with poor fusional vergence amplitudes and vergence facility. Objective eye movement recording was also administered at the initial examination. Convergence and divergence 4º symmetrical step vergences as well as peak velocity, time to peak velocity, latency response amplitude and settling time were assessed. Following treatment with office-based vision therapy, both clinical and objective eye movement measurements were evaluated.

Clinically meangingful changes were found in negative fusional vergence at near (2Δ to 8Δ) and vergence facility at near (0 to 5 cpm). Objective measurements revealed a change in peak velocity (15.95º /sec to 31.02º /sec, p = .004), response accuracy (1.56 degrees to 3.87 degrees, p=.01), latency (0.24 sec to 0.18 sec), and time to peak velocity (0.74 sec to 0.42 sec) to 4º symmetrical divergence step stimuli. 

Conclusion:This case study provides the first report of significant changes in objective measures of divergence after vision therapy for esophoria. 

Affiliation of Co-Authors Pennsylvania College of Optometry at Salus University, New Jersey Institute of Technology