Comparison of Two Treatments for Strabismus Correction: Botulinum Toxin A Associated to Surgery and Surgery Alone

Study Overview
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Brief Summary
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Two different treatments were given to large angle horizontal strabismus (eso and exotropia) adult patients who agree to participate of the study. Inform consents were required for participants. Group 1 (12 patients) received conventional recess-resect surgery plus intraoperative injection of botulinum toxin A (5U). Group 2 (11 patients) received only conventional recess-resect surgery. The patients were randomly located in one of the groups. The angles of horizontal deviation were compared between the groups before and six months after treatment.

Detailed Description
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Patients underwent recess/resection surgery on the non-fixating eye using conventional technique under local anesthesia. The extent of surgery was determined based on our usual amounts. Before re-attaching the recessed muscle to the sclera, 5 units of botulinum toxin in 0.1 ml of hyaline solution were, or 0.1 ml of hyaline solution alone were was injected into the posterior muscle belly by the surgeon who was unaware of the contents of each syringe.

Official Title
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Surgery Associated to Intraoperative Botulinum Toxin A for Large Angle Horizontal Strabismus: a Pilot Study

Conditions
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Esotropia, Exotropia

Intervention / Treatment
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* Drug: Botulinum Toxin Type A
* Drug: saline solution


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: adults with large angle horizontal strabismus Exclusion Criteria: oblique muscle disfunction previous strabismus surgery dissociated vertical deviation paretic or restrictive deviation

Ages Eligible for Study
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Minimum Age: 20 Years
Maximum Age: 60 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

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: Botulinum toxin plus surgery<br>Intraoperative injection of 5U (0.1 ml) of Botulinum Toxin will be given to the recessed muscle during surgery | Drug: Botulinum Toxin Type A<br>* injection of 5U in 0.1ml of saline solution will be given to the recessed muscle<br>* Other names: BTA;|
| Placebo Comparator: Saline solution plus surgery<br>Saline solution (0,1 ml)will be given to the recessed muscle during surgery procedure | Drug: saline solution<br>* injection of 0,1ml of saline solution will be given to the recessed muscle<br>* Other names: saline;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| percentage of decrease of the initial angle of strabismus | The percentages of decrease of the initial angle of strabismus were accessed by subtracting the final deviation of the initial deviation, dividing the result by the initial deviation and multiplying it by 100. | 6 to 12 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| frequency of induced blepharoptosis | The presence of induced blepharoptosis was detected by simple inspection and was reported as positive or negative. | From the first to the last post operative day of follow up | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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strabismus surgery, botulinum toxin, esotropia, exotropia, blepharoptosis