Botulinum Toxin A for the Treatment of Keratoconus

Study Overview
=================
Brief Summary
-----------------
The purpose of this study is to associate the use of botulinum toxin type A for patients with keratoconus to demonstrate that tension eyelid has an important role in disease progression.

Detailed Description
-----------------
Subcutaneous injection of botulinum toxin type A will be performed at two points in a nasal and temporal extent of the orbicularis muscle of a group of patients with keratoconus (Botulinum toxin A group).The idea is to evaluate the change in palpebral fissure in patients from group botulinum toxin A over a period of 18 months.The measurements of the palpebral fissure will be performed by the Image J (version 1.34s) program, developed by the National Institutes of Health (USA).The unit of measure is the millimetre.The patients of the botulinum toxin A group will be compared with a control group, without any intervention.

Official Title
-----------------
Botulinum Toxin Type A for Keratoconus

Conditions
-----------------
Keratoconus

Intervention / Treatment
-----------------
* Procedure: Subcutaneous injection of botulinum toxin type A
* Drug: Botulinum Toxin Type A


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: patients with documented keratoconus best-corrected visual acuity measurable at refraction test age between 10-40 years good health understand the procedure and its limitations Exclusion Criteria: only one functional eye previous ocular surgery concurrent corneal infection and other ocular diseases that modified the visual acuity known allergy to botulinum toxin pregnancy poor collaboration for performing the examinations and the procedure

Ages Eligible for Study
-----------------
Minimum Age: 10 Years
Maximum Age: 40 Years

Sexes Eligible for Study
-----------------
All

Accepts Healthy Volunteers
-----------------
No

Study Plan
=================
How is the study designed?
-----------------

Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Botulinum toxin type A<br>The group that will be subjected to the injection of botulinum toxin (subcutaneous injection of botulinum toxin type A).Subcutaneous botulinum toxin A injection will be performed in this group, (2.5 units per point application), at two points in a nasal and temporal extent of the orbicularis muscle. | Procedure: Subcutaneous injection of botulinum toxin type A<br>* Subcutaneous injection of botulinum toxin type A (2.5 units per application point) at two points in a nasal and temporal extent of the orbicularis muscle will be performed in the Botulinum toxin type A group.<br>Drug: Botulinum Toxin Type A<br>* 2.5 units per point of application at two points in a nasal and temporal extent of the orbicularis muscle.<br>* Other names: Botox (Allergan);|
| No Intervention: Control<br>The group that will not be subjected to any intervention. | |

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Measurement of the palpebral fissure | We will evaluate the change in palpebral fissure (unit of measure=millimetre)by 18 months.These time points will be included:baseline, 3, 6, 12 and 18 months. | Eighteen months. | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Corneal topography | We will evaluate corneal topography [flattest keratometry, steepest keratometry and average keratometry(unit of measure=diopters)]by 18 months.These time points will be included:baseline, 3, 6,12 and 18 months. | Eighteen months. | 

 Terms related to the study
=================
Keywords Provided by Centre Hospitalier Valida
-----------------
Keratoconus, Tetanus toxin