Corneal Cross Linking and Topography Guided Excimer Laser Treatment

Study Overview
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Brief Summary
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Topography guided laser treatment enables the surgeon to correct higher order aberrations in corneas with irregular astigmatism. Several case reports and small uncontrolled trials have been published on the combination of this treatment with corneal cross linking (CCL) in patients with ectatic corneal diseases. This randomized study will evaluate the safety and efficacy of a combined treatment of corneal cross linking with a partial topography guided excimer laser treatment in eyes with progressive ectatic corneal diseases.

Official Title
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Topography Guided Excimer Laser Surface Ablation in Combination With Corneal Cross-linking (CCL) in Patients With Progressive Ectatic Corneal Disorders.

Conditions
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Keratoconus, Pellucid Marginal Degeneration

Intervention / Treatment
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* Other: Topography guided Excimer Laser treatment and Corneal Cross Linking
* Other: Corneal Cross Linking


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Signed informed consent Patient age 18 - 40 years Documented progressive corneal ectatic disease except post LASIK/LASEK ectasia Exclusion Criteria: Allergy to one of the used substances Tendency towards excessive scar formation Pregnancy Rheumatic diseases Central corneal thickness below 450 µm Active infection of the study eye Previous corneal surgery of the study eye

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 40 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: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Corneal Cross Linking<br>Patients will receive a standard corneal cross linking treatment | Other: Corneal Cross Linking<br>* A standard corneal cross linking procedure will be performed in this arm.<br>|
| Experimental: Corneal Cross Linking and Topo Laser<br>Patients will receive a topography guided laser treatment in combination with a standard corneal cross linking treatment in the same session. | Other: Topography guided Excimer Laser treatment and Corneal Cross Linking<br>* A topography guided excimer laser treatment will be performed prior to CCL in one session.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Safety (Pachymetry, K-readings) |  | 1 year | 
| uncorrected visual acuity (UVCA) |  | 1 year | 
| best corrected visual acuity (BCVA) |  | 1 year | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Progression of ectatic disease (by use of maximum keratometry readings = Kmax) |  | 1 year | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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corneal cross linking, topography guided excimer laser, Keratoconus, Pellucid marginal degeneration, Post Excimer ectasia