A Prospective Study of Femtosecond Laser Intracorneal Lensectomi

Study Overview
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Brief Summary
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The purpose of this study is to compare visual acuity, safety, predictability, corneal biomechanics, dry eyes, and nerve-morphology after all femtosecond laser refractive lenticule extraction. Approximately 30 to 40 patients with moderate to high myopia will randomly (after ocular dominance) receive ReLEx flex in one eye, and ReLEx smile in the other.

Official Title
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A Prospective Study of Femtosecond Laser Intracorneal Lensectomi in Treatment of Moderate to High Myopia

Conditions
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Myopia, Astigmatism

Intervention / Treatment
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* Device: Carl Zeiss Meditech VisuMax laser


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: 25 to 45 years, moderate to high myopia with astigmatism =< 2 D, otherwise eye healthy, CDVA of 0.8 or better (Snellen). Exclusion Criteria: systemic or ocular disease or previous eye surgery, thin cornea, a difference of more than 2 D myopia in the eyes of each subject.

Ages Eligible for Study
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Minimum Age: 25 Years
Maximum Age: 45 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
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Carl Zeiss Meditech VisuMax laser - ReLEx flex<br>>30 patients will receive treatment for myopia with a VisuMax femtosecond laser from Carl Zeiss. The laser can cut with two different settings, called ReLEx flex and ReLEx smile. One eye will recieve ReLEx flex, and the other ReLEx smile | Device: Carl Zeiss Meditech VisuMax laser<br>* Refractive lenticule extraction (ReLEx) with the Carl Zeiss Meditech VisuMax laser<br>* Other names: Refractive lenticule extraction, ReLEx;|
| Active Comparator: Carl Zeiss Meditech VisuMax laser - ReLEx smile<br>>30 patients will receive treatment for myopia with a VisuMax femtosecond laser from Carl Zeiss. The laser can cut with two different settings, called ReLEx flex and ReLEx smile. One eye will recieve ReLEx flex, and the other ReLEx smile | Device: Carl Zeiss Meditech VisuMax laser<br>* Refractive lenticule extraction (ReLEx) with the Carl Zeiss Meditech VisuMax laser<br>* Other names: Refractive lenticule extraction, ReLEx;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Visual acuity | Using ETDRS charts, both uncorrected and corrected distance visual acuity, along with visual acuity using the FrACT contrast chart | up to 6 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| refractive predictability | Optometrists measure refraction at follow-up-examinations, and the refraction 6 monhts after surgery will be compared to the target refraction to calculate refractive predictability | Pre-surgery, 1 week, 1 month, 3 months, 6 months | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Myopia, refractive surgery, all femtosecond laser, ReLEx flex, ReLEx smile