Treatment of Keratoconus With PALK Versus PK

Study Overview
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Brief Summary
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The purpose of this study is to evaluate the visual results of patients with keratoconus treated with one of two techniques: penetrating keratoplasty (PK) vs. pachymetry and Excimer laser assisted lamellar keratoplasty (PALK).

Official Title
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Treatment of Keratoconus With Pachymetry Assisted Laser Keratoplasty (PALK) Versus Penetrating Keratoplasty (PK)

Conditions
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Keratoconus

Intervention / Treatment
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* Procedure: Penetrating keratoplasty
* Procedure: Pachymetry and Excimer laser assisted lamellar keratoplasty
* Drug: Treatment posterior to surgery


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Diagnosis of keratoconus grades III or IV in the Amsler Krumeich classification. Need of surgical procedure No endothelial scar Best corrected visual acuity <20/40 Contact lens intolerance Imagenological map pachymetric acquisition over 90% at 9 mm corneal diameter Exclusion Criteria: Contraindication for any of the techniques evaluated. Requiring additional surgical procedures. Diagnostic of other ectasia that were not primary keratoconus.

Ages Eligible for Study
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Minimum Age: 18 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: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Penetrating keratoplasty<br>Conventional penetrating keratoplasty technique | Procedure: Penetrating keratoplasty<br>* Conventional Penetrating keratoplasty technique<br>Drug: Treatment posterior to surgery<br>* Fluoroquinolone topical antibiotic (Moxifloxacin, Vigamox) and topical steroid (Prednisolone Acetate Ophthalmic Suspension, Pred Forte)<br>|
| Experimental: PALK<br>Pachymetry and Excimer laser assisted lamellar keratoplasty | Procedure: Pachymetry and Excimer laser assisted lamellar keratoplasty<br>* Ablation profile focusing on topography and pachymetry with Schwind Amaris excimer laser<br>Drug: Treatment posterior to surgery<br>* Fluoroquinolone topical antibiotic (Moxifloxacin, Vigamox) and topical steroid (Prednisolone Acetate Ophthalmic Suspension, Pred Forte)<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Visual acuity | Uncorrected and corrected distance visual acuity | 6 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Corneal measurements: pachymetry | Evaluation of the pachymetric maps with a Scheimpflug-Placido device (Sirius). Measurement in microns | 6 months | 
| Corneal aberrometry: Coma, spherical aberration and trefoil | Evaluation of the corneal aberrations including coma, spherical aberration and trefoil, with a Scheimpflug-Placido device (Sirius) | 6 months | 
| Corneal measurements: anterior and posterior elevation | Evaluation of the elevation (anterior and posterior), maps with a Scheimpflug-Placido device (Sirius). Measurement in diopters | 6 months | 
| Corneal measurements: keratometries. | Evaluation of the keratometric map with a Scheimpflug-Placido device (Sirius). Measurement in diopters | 6 months | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Keratoconus