Evaluation of Topical Riboflavin Exposed to UVA Radiation and Implantation of Corneal Ring

Study Overview
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Brief Summary
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The purpose of this study is to postpone the corneal transplantation in keratoconus and promote the stiffness of the cornea across the riboflavin-UVA corneal collagen crosslinking , and after, corneal ring surgery.

Detailed Description
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Keratoconus is a progressive disease where cornea is thin and has a higher curvature.In early conditions, it may be corrected by glasses or contact lens.When these possibilities are not more possibles, it may be corrected by corneal ring surgery ore corneal transplantation depending your degree. In this study, the patients with a degree of keratoconus on I or II, will be submitted to corneal collagen crosslinking and then a corneal ring surgery. The corneal collagen crosslinking promote the stiffness of the cornea across the riboflavin-UVA irradiation, avoid the progression of the keratoconus.After three months of crosslinking, these patients will be submitted a corneal ring surgery. These patients will be allowed by two years and various exams will realized them.

Official Title
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Evaluation of Topical Riboflavin Exposed to UVA Radiation and Implantation of Intrastromal Corneal Ring for Treatment of Keratoconus and Others Irregulars Astigmatisms.

Conditions
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Keratoconus

Intervention / Treatment
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* Procedure: Corneal collagen crosslinking


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients with keratoconus Patients that aren't using contact lenses Pachymetry more than 400Um Best visual acuity less or equal 20/30 Exclusion Criteria: Ocular surgeries before Other eye diseases Corneal curvature more than 65 dioptres
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: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Sham Comparator: Eyedrop<br> | Procedure: Corneal collagen crosslinking<br>* The patients will be submitted to corneal collagen crosslinking, that consists: Instillation of riboflavin eyedrop in the cornea for thirty minutes, and after, the patient will stay under the Crosslinking equipment, for more thirty minutes, also receiving riboflavin eyedrop.<br>* Other names: Corneal collagen crosslinking.;|
| Active Comparator: Crosslinking<br>The patients will be submitted to corneal collagen crosslinking, by use riboflavin eyedrop with UVA light. | Procedure: Corneal collagen crosslinking<br>* The patients will be submitted to corneal collagen crosslinking, that consists: Instillation of riboflavin eyedrop in the cornea for thirty minutes, and after, the patient will stay under the Crosslinking equipment, for more thirty minutes, also receiving riboflavin eyedrop.<br>* Other names: Corneal collagen crosslinking.;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Refractive data, visual acuity, topography patterns, pachymetry measurements. |  | Two years | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Anterior segment tomography data, corneal biomechanics, impression cytology. |  | Two years | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Keratoconus, riboflavin, cornea, crosslinking