The Effect of Slanted Recession of Horizontal Muscle on Horizontal Strabismus With Abnormal Accommodative Convergence /Accommodation Ratio (AC/A)

Study Overview
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Brief Summary
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Different methods was tried to treat high AC/A strabismus cases;such as prescription of bifocal glasses in esotropia,recession of horizontal muscles with posterior fixation sutures,more recession than needed for far deviation(augmented recession),recession and pulley fixation and slant recession. Different results was reported for any type of above methods. In recent studies,slanted recession was applied for high AC/A in esotropic cases and success rate of 67% was reported.but there was no unanimity for procedure of choice. Since slant recession method is simpler and has low side effect than the other methods,therefore in this study the investigators want to peruse the outcome of this method on high AC/A horizontal strabismus.

Official Title
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The Effect of Slanted Recession of Horizontal Muscle on Horizontal Strabismus With Abnormal Accommodative Convergence /Accommodation Ratio (AC/A)

Conditions
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Horizontal Strabismus With High AC/A Ratio

Intervention / Treatment
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* Procedure: conducting the slanted recession technique on the superior and inferior poles
* Procedure: conducting the augmented recession technique on the muscle


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: all patients with horizontal strabismus that the different between far deviation and near deviation is more than 10 pd Exclusion Criteria: all patients who had history of surgery on horizontal muscles and patients with pseudo high AC/A ratio.

Ages Eligible for Study
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Minimum Age: 6 Years
Maximum Age: 80 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: conducting the slanted recession technique<br>conducting the slanted recession technique on the superior and inferior poles of the muscle based on far and near deviations. | Procedure: conducting the slanted recession technique on the superior and inferior poles<br>* conducting the slanted recession technique on the superior and inferior poles of the muscle based on far and near deviations.<br>|
| Active Comparator: conducting the augmented recession technique on the muscle<br>conducting the augmented recession technique on the muscle for 1 to 1.50 mm more compared with the standard method. | Procedure: conducting the augmented recession technique on the muscle<br>* conducting the augmented recession technique on the muscle for 1 to 1.50 mm more compared with the standard method.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| far-near deviation difference | difference between the far and near deviations | 90 days after surgery | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| success rate of surgery | in cases with difference of far and near deviation less than 10 prism diopters | 90 days after surgery |