Laser In-situ Keratomileusis With Crosslinking Compared to Conventional LASIK in Patients With High Myopia

Study Overview
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Brief Summary
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The objectives of this study are to evaluate the safety and efficacy of a treatment regimen for high myopia and myopic astigmatism: LASIK followed by crosslinking performed with the KXL Crosslinking-System and VibeX Xtra (Riboflavin Ophthalmic Solution, Avedro, USA), as compared to LASIK alone, with regards to regression of refractive outcome, as measured by manifest refraction spherical equivalent (MRSE) and keratometry.

Detailed Description
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This is a controlled study of the safety and efficacy of the KXL System and VibeX Xtra (Riboflavin Ophthalmic Solution, Avedro, USA) for performing crosslinking in eyes undergoing LASIK for high myopia or myopic astigmatism. Each subject will have bilateral LASIK performed and one eye will be randomized to undergo LASIK followed by crosslinking. Subjects will undergo bilateral LASIK. Following randomisation one eye of each subject will be treated with VibeX Xtra (Riboflavin Ophthalmic Solution) following LASIK and will be irradiated with the KXL System at 30 mW/cm2 intensity for 90 seconds continuous UV-A light treatment for a total radiant exposure of 2.7 J /cm2. All eyes will be assessed at 1 day, 1, 3, 6, and 12 months after treatment.

Official Title
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A Controlled Evaluation of the Safety and Efficacy of Laser In-situ Keratomileusis With Crosslinking (XtraLASIK) Compared to Conventional LASIK (convLASIK) in Patients With High Myopia

Conditions
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Myopia, Myopic Astigmatism, Crosslinking, Corneal Ectasia, Myopic Regression

Intervention / Treatment
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* Procedure: LasikXtra
* Procedure: LASIK


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: eligible for bilateral myopic fs-LASIK with -6.00 to -12.00 D (diopters) with a maximum of 5.00 D astigmatism age > 18 years provided written informed consent difference between the MRSE and cycloplegic SE less than 0.75 D MRSE needed to be stable for the last 12 months (<0.5 D). Exclusion Criteria: prior corneal surgery, forme fruste or manifest keratoconus, history of corneal scarring, melting, ulceration repeating inflammations of the eye taking vitamin C 1 week prior to the treatment

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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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
Interventional Model Description: Prospective, randomized, intra-patient controlled, clinical trial
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Other: Study group<br>LASIK followed by intraoperative application of riboflavin under the flap and crosslinking after reposition of the flap. | Procedure: LasikXtra<br>* By randomized selection, one eye was treated with the LASIK Xtra procedure that consists of fs-LASIK treatment combined with intraoperative accelerated continuous UV-riboflavin crosslinking. After laser ablation, the corneal bed under the flap was coated with riboflavin, rinsed with saline solution, and after 90 seconds the corneal flap was repositioned. The eye was irradiated at 30 mW/cm2 for 90 seconds with continuous UVA.<br>|
| Other: Control group<br>LASIK only | Procedure: LASIK<br>* Femtosecond-assisted preparation of a corneal flap and subsequently excimer-laser ablation of corneal stroma. Repositioning of the corneal flap and installation of a therapeutic contact lens.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| uncorrected distant visual acuity | uncorrected distant visual acuity (logarithmic minimum angle of resolution) | 12 months postoperative | 
| best spectacle corrected distant visual acuity | best spectacle corrected distant visual acuity (logarithmic minimum angle of resolution) | 12 months postoperative | 
| spherical equivalent | spherical equivalent (diopter) | 12 months postoperative | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| endothelial cell count | endothelial cell count (number of cells/ mm2) | 12 months postoperative | 
| Corneal thickness | Corneal thickness (micro millimeter) | 12 months postoperative | 
| Subjective visual quality | Questionnaire regarding subjective optical quality (scale from 0 - 100; 0 = minimal, 100 = maximum) | 12 months postoperative |