Femtosecond Laser-assisted Anterior Lamellar Keratoplasty

Study Overview
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Brief Summary
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The purpose of the study is evaluating safety and clinical efficiency of full femtosecond laser-assisted anterior lamellar keratoplasty (FS-ALK) for curing patients with keratoconus and corneal opacities

Detailed Description
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Keratoplasty is the most widely spread tissue transplantation procedure. Although penetrating keratoplasty (PKP) is still commonly used for curing corneal dystrophy and opacities of different genesis, lamellar techniques provide significant advantages in terms of safety and predictability. Al in all 13 FS-ALK procedures were performed for 11 eyes with advanced keratoconus and 2 eyes with superficial corneal scattering Before and after surgery uncorrected visual acuity (UCVA), best spectacle-corrected visual acuity (BSCVA), postoperative astigmatism, endothelial cell loss, central cornea thickness, residual recipient's tissue thickness, corneal hysteresis (CH) and corneal resistance factor (CFR) were evaluated . At 1-year follow-up Confoscan investigation of donor-recipient interface was performed. All FS-ALK procedures were performed with Intralase FS 60kHz femtosecond laser in a following way. At first a 80% thickness corneal graft was prepared. Then maximum thickness recipients corneal dissection was performed according to OCT (optical coherence tomography) data and superficial tissue was removed. Transplant was fixed in a resulted bed by continuous suture.

Official Title
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Femtosecond Laser-assisted Anterior Lamellar Keratoplasty

Conditions
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Keratoconus, Corneal Opacity

Intervention / Treatment
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* Procedure: FS-ALK (Femtolaser-assisted anterior lamellar keratoplasty)


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Advanced keratoconus or stromal corneal scattering Normal endothelial cell density Exclusion Criteria: Acute keratoconus in the anamnesis Low endothelial cell density Age under 18 years

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 52 Years


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: FS-ALK<br>Femtosecond laser-assisted maximum thickness anterior lamellar keratoplasty (FS-ALK) was performed for 11 eyes of 11 patients with advanced keratoconus and 2 eyes of 2 patients with superficial corneal scattering. | Procedure: FS-ALK (Femtolaser-assisted anterior lamellar keratoplasty)<br>* The procedure was a non-penetrating transplantation of 80% thickness corneal graft<br>* Other names: Femto-ALK;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Mean endothelial cell loss |  | 12 months after surgery | 
| Mean postoperative astigmatism |  | 12 months after surgery | 
| UCVA (uncorrected visual acuity) |  | 12 months after surgery | 
| BSCVA (best spectacle-corrected visual acuity) |  | 12 months after surgery | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Corneal hysteresis | Evaluation of biomechanical qualities of the cornea | 12 months after surgery | 
| Corneal resistance factor | Evaluation of biomechanical qualities of the cornea | 12 months after surgery | 
| Central corneal thickness | measured by OCT (optical coherence tomography - Optovue) | 12 months after surgery | 
| Residual recipient's tissue thickness | measured by OCT (optical coherence tomography - Optovue) | 12 months after surgery | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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femtosecond laser, anterior lamellar keratoplasty, atomic-force microscopy