Intrastromal Correction of Ametropia by a Femtosecond Laser

Study Overview
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Brief Summary
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This study evaluates the intrastromal correction of ametropia with a femtosecond laser made by 20/10 PERFECT VISION. This laser generates a beam of ultrashort, infrared pulses which enables very precise cuts in the cornea. By these cuts lamellae of the cornea are separated locally, and in the consequence the curvature of the cornea is changed, and the correction of the diagnosed ametropia can be achieved. On the contrary to cuts which are generated with a sharp knife, the cuts generated when using a laser can be generated just inside the cornea without opening the surface of the cornea. This means the procedure is minimal-invasive. The study hypothesis is: Different types of ametropia can be corrected safely and on long-term by intrastromal cuts.

Official Title
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Intrastromal Correction of Ametropia by a Femtosecond Laser

Conditions
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Presbyopia, Myopia, Hyperopia, Astigmatism

Intervention / Treatment
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* Device: Intrastromal Correction of Presbyopia
* Device: Intrastromal correction of Myopia
* Device: Intrastromal Correction of Hyperopia
* Device: Intrastromal Correction of Myopia incl. Astigmatism
* Device: Intrastromal Correction of Hyperopia incl. Astigmatism


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: age: > 18 years stable distance refraction for at least one year (i.e. a maximum change of 0.5 D) in the case of presbyopia: minimum near add +2D to + 4D in the case of myopia or hyperopia (without astigmatism): minimal 1D and maximum 3D in the case of myopia or hyperopia (with astigmatism): spherical equivalent of minimal 1D and maximum 3D BSCVA of the eye to be treated >= 0.63 patients are willing and in such conditions to come to the follow-up exams no further ocular pathologies Exclusion Criteria: age: < 18 years refraction less than +/- 1 D or higher than +/- 3 D (not valid for presbyopia patients) minimal pachymetry of < 500µm K-mean < 37 D or > 60 D Difference (K-max minus K-min) > 5D Difference cycloplegic refraction to subjective refraction more than 1 D (valid only for hyperopia correction) patients with previous intraocular or corneal surgeries (e.g. post-LASIK or PRK patients). Exemption: standard cataract surgery. patients with one or more of the following ocular pathologies: keratokonus corneal scars transplanted cornea disorders of wound healing trauma glaucoma epilepsia nystagmus lack of concentration other complicated illnesses diabetes mellitus instable K-readings as a sign of instable cornea weakness of connective tissue sensitivity against the drugs used in the study continuous wearing of contact lenses before the pre-exam, and before the surgery. At least 14 days before these dates patients must abstain from wearing CL. patients in pregnancy or during lactation patients who take part in another clinical trial

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
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: 1 / Presbyopia<br>Presbyopic patients, slightly hyperopes | Device: Intrastromal Correction of Presbyopia<br>* Applying defined, pre-programmed patterns (e.g. rings and/or radial cuts)into the human eye cornea. It is a minimal-invasive procedure which changes the topography of the cornea and by that the refraction ability.<br>* Other names: - Patient Interface;|
| Experimental: 2 / Myopia<br>Myopic patients without Astigmatism | Device: Intrastromal correction of Myopia<br>* Applying defined, pre-programmed patterns (e.g. rings and/or radial cuts)into the human eye cornea. It is a minimal-invasive procedure which changes the topography of the cornea and by that the refraction ability.<br>* Other names: FEMTEC Laser System;|
| Experimental: 3 / Hyperopia<br>Hyperope patients without Astigmatism | Device: Intrastromal Correction of Hyperopia<br>* Applying defined, pre-programmed patterns (e.g. rings and/or radial cuts)into the human eye cornea. It is a minimal-invasive procedure which changes the topography of the cornea and by that the refraction ability.<br>* Other names: FEMTEC Laser System;|
| Experimental: 4 / Myopia with Astigmatism<br>Myopic patients incl. Astigmatism | Device: Intrastromal Correction of Myopia incl. Astigmatism<br>* Applying defined, pre-programmed patterns (e.g. rings and/or radial cuts)into the human eye cornea. It is a minimal-invasive procedure which changes the topography of the cornea and by that the refraction ability.<br>* Other names: FEMTEC Laser System;|
| Experimental: 5 / Hyperopia with Astigmatism<br>Hyperope patients incl. Astigmatism | Device: Intrastromal Correction of Hyperopia incl. Astigmatism<br>* Applying defined, pre-programmed patterns (e.g. rings and/or radial cuts)into the human eye cornea. It is a minimal-invasive procedure which changes the topography of the cornea and by that the refraction ability.<br>* Other names: FEMTEC Laser System;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Prove safety and effectiveness as well as improvement in near visual acuity performance and increase in near visual acuity. |  | 3 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Validate the 3 months results |  | 6 months | 
| Prove stability of distance visual acuity and safety of the procedure regarding infections and inflammatory response as well as corneal endothelial cell counts. |  | 6 months |