KLEx Versus FS-LASIK for the Treatment of Myopia and Compound Myopic Astigmatism

Instituto de Oftalmología Fundación Conde de Valenciana

Status: Not yet enrolling

Conditions: Myopia; Astigmatism; Myopic Astigmatism

Treatments: Procedure: KLEx; Procedure: FS-LASIK procedure

Study type: Interventional

Funder types: Other

Identifiers

NCT06477081

CI-017-2024

Details and patient eligibility

About

FemtoLASIK is a type of laser eye surgery used to correct vision problems such as nearsightedness, farsightedness, and astigmatism. It involves two main steps: creating a flap and reshaping the cornea. Refractive lenticule extraction, (KLEx) is another laser eye surgery method to correct vision issues, which involves creating and extracting a lenticule without the need of a flap. The investigators will evaluate and compare the efficacy and safety of these two procedures.

Full description

Keratorefractive lenticule extraction (KLEx) is a refractive surgery technique that does not require the creation of a flap to correct the defects. The potential advantages of this technique are related to the absence of a flap, which could make it the gold standard of refractive surgery. On the other hand, femtosecond-assisted laser in-situ keratomileusis (FS-LASIK) is the most widely practiced refractive surgery worldwide, as it offers excellent visual outcomes but does require the creation of a flap to correct the defects. The objective of this study is to evaluate the effectiveness and safety of KLEx versus FS-LASIK as a treatment option in patients with myopia or compound myopic astigmatism. This is a prospective randomized study. A total of 80 participants will be randomized into two groups, the KLEx group and FS-LASIK group. Following randomization, participants will be followed on the first day after the surgery, 1 week, 1, 3, 6, and 12 months. The primary outcome is the refractive predictability at every postoperative point after surgery, which is the proportion of the number of eyes achieving a postoperative spherical equivalent within ± 0.5 diopters of the intended target. Secondary outcome parameters include quality vision measurements, refraction, visual acuity, and adverse events.

Enrollment: 80 estimated patients

Sex: All

Ages: 21+ years old

Volunteers: Accepts Healthy Volunteers

Inclusion criteria

• Age 21 years or older
• Corneal tomography without alterations
• Myopia between -0.50 and -12.00 D
• Astigmatism between -0.50 and -6.00 D

Exclusion criteria

• Previous eye surgeries
• Pregnancy
• Progressive or unstable myopia and/or compound myopic astigmatism
• Ocular surface disease

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: Triple Blind

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80 participants in 2 patient groups

FemtoLASIK

Active Comparator group

Description:

For the FS-LASIK technique, the following steps will be followed: application of topical anesthesia to mitigate discomfort and pain throughout the procedure, and the patient will be covered with a sterile drape. Subsequently, the patient will be aligned to artificially flatten the entire corneal surface, ensuring head stability with a slight tilt to optimize surgical access and avoid nasal interference. The femtosecond laser system use will be the ATOS operating system (Schwind eye-tech-solutions, Mainparkstraße 6-10, 63801 Kleinostheim, Germany), which is responsible for creating a corneal incision to create the flap, with controlled precision to ensure proper separation of corneal layers. The excimer laser will be the Amaris (Schwind eye-tech-solutions, Mainparkstraße 6-10, 63801 Kleinostheim, Germany), responsible for performing refractive correction on the cornea through selective photoablation. Following photoablation, the flap will be carefully repositioned, and upon completion

Treatment:

Procedure: FS-LASIK procedure

Keratorefractive lenticule extraction

Active Comparator group

Description:

For the KLEx technique, the following steps will be followed: after topical anesthesia, a sterile drape is placed over the patient, and a speculum is inserted into the eye, centered, and aligned with a curved interface cone before applying suction. The laser used will be the ATOS operating system (Schwind eye-tech-solutions, Mainparkstraße 6-10, 63801 Kleinostheim, Germany), which performs photo-dissection starting from the posterior surface of the refractive lenticule, followed by the creation of the lenticule edge. The anterior surface of the refractive lenticule is formed by extending beyond the posterior diameter of the lenticule by 0.5 mm to form the anterior flap, followed by a peripheral cut. Specific FS laser parameters are employed for each patient. Subsequently, the suction is released, and a Siebel spatula is used to separate and reflect the flap. Finally, the refractive lenticule is extracted using toothless forceps through the small incision. Once the procedure is complet

Treatment:

Procedure: KLEx