Comparison of Three Vision Therapy Approaches for Convergence Insufficiency

Study Overview
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Brief Summary
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We compared the effectiveness of three active vision therapy approaches for convergence insufficiency (CI). Patients with eligible criteria and symptomatic CI were included in a prospective study and randomly allocated into three groups. In the home-based vision orthoptic therapy (HBVOT) group, patients were trained to do the pencil push-ups procedure 15 minutes per day, five days a week. In the office-based vision orthoptic therapy (OBVOT) group, 60 minutes of orthoptic therapy using a major amblyoscope twice weekly with additional home orthoptic therapy was prescribed. For the augmented office-based vision orthoptic therapy (AOBVOT) group, orthoptic exercises using three diopter over-minus lenses and a base out prism, in addition to major amblyoscope and additional home reinforcement was prescribed in the same period of time.

Official Title
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Comparison of Three Vision Therapy Approaches for Convergence Insufficiency

Conditions
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Comparison of Three Vision Therapy Approaches for Convergence Insufficiency

Intervention / Treatment
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* Procedure: trained to do the pencil push-ups procedure
* Procedure: using a major amblyoscope twice weekly with additional home orthoptic therapy
* Procedure: using three diopter over-minus lenses and a base out prism


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: patients between 15 and 35 years of age who have symptomatic CI using the Convergence Insufficiency Symptom Survey (CISS) scoring system. best-corrected visual acuity ≥ 20/25 exophoria at near at least 4 prism diopters (△) greater than at distance near point of convergence more than 6.0 cm break insufficient positive fusional vergence (PFV) (failing Sheard's criterion or PFV ≤ 15 △ base-out) at near distance. Exclusion Criteria: amblyopia (VA worse than 20/30 in each eye), presence of manifest strabismus, history of ocular surgery, any systemic disorder, anisometropia of more than 1.5 diopter of myopia or hyperopia or significant refractive error, and nystagmus and usage of medications that may impair accommodation or convergence. ,ocular surface abnormalities or history of ocular allergy or those who had previously been treated for CI

Ages Eligible for Study
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Minimum Age: 15 Years
Maximum Age: 35 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: home-based vision orthoptic therapy (HBVOT) group<br>In the home-based vision orthoptic therapy (HBVOT) group, patients were trained to do the pencil push-ups procedure 15 minutes per day, five days a week | Procedure: trained to do the pencil push-ups procedure<br>* 15 minutes per day, five days a week<br>|
| Active Comparator: office-based vision orthoptic therapy (OBVOT) group<br>In the office-based vision orthoptic therapy (OBVOT) group, 60 minutes of orthoptic therapy using a major amblyoscope twice weekly with additional home orthoptic therapy was prescribed | Procedure: using a major amblyoscope twice weekly with additional home orthoptic therapy<br>* 60 minutes of orthoptic therapy using a major amblyoscope twice weekly with additional home orthoptic therapy was prescribed.<br>|
| Active Comparator: augmented office-based vision orthoptic therapy (AOBVOT) group<br>For the augmented office-based vision orthoptic therapy (AOBVOT) group, orthoptic exercises using three diopter over-minus lenses and a base out prism, in addition to major amblyoscope and additional home reinforcement was prescribed in the same period of time. | Procedure: using three diopter over-minus lenses and a base out prism<br>* For the augmented office-based vision orthoptic therapy (AOBVOT) group, orthoptic exercises using three diopter over-minus lenses and a base out prism, in addition to major amblyoscope and additional home reinforcement was prescribed in the same period of time.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| symptomatic convergence insufficiency | A symptomatic score was an average score of 16 or higher on the CISS(conv-insuff-sympt-scove) | one month |