Early Changes Among FLEx, LASIK and FS-LASIK

NCT ID: NCT02551796

Last Updated: 2016-06-14

Study Results

Results pending

The study team has not published outcome measurements, participant flow, or safety data for this trial yet. Check back later for updates.

Basic Information

Get a concise snapshot of the trial, including recruitment status, study phase, enrollment targets, and key timeline milestones.

Recruitment Status

COMPLETED

Clinical Phase

NA

Total Enrollment

75 participants

Study Classification

INTERVENTIONAL

Study Start Date

2015-09-30

Study Completion Date

2016-04-30

Brief Summary

Review the sponsor-provided synopsis that highlights what the study is about and why it is being conducted.

To evaluate the short-term changes in ocular surface measures and tear inflammatory mediators after lenticule extraction (FLEx), laser in situ keratomileusis (LASIK) and femtosecond laser-assisted laser in situ keratomileusis (FS-LASIK) procedures.

Detailed Description

Dive into the extended narrative that explains the scientific background, objectives, and procedures in greater depth.

Laser in situ keratomileusis (LASIK) with a microkeratome has been accepted wildly in the past 20 years. Gradually, laser in situ keratomileusis with a femtosecond laser-created flap (FS-LASIK)has been a popular ophthalmic procedure for the correction of refractive error. This first all-in-one FS-laser system was designed to perform the refractive lenticule extraction (ReLEx) procedures, femtosecond lenticule extraction (FLEx).They have the same feature: corneal flap.

Ocular surface disruption during corneal refractive surgery is commonly considered to be closely related to the development of dry eye. Multiple etiologies contribute to this ocular surface disruption, including the flap creation and stromal ablation involved in previous refractive surgery techniques. Corneal nerve damage has been considered the main cause of dry eye, due to disrupted afferent sensory nerves, reduced blink reflex, and increased tear evaporation leading to tear film instability. In addition, postoperative inflammatory mediator fluctuations are also a key factor related to ocular surface damage. Extensive research has described the effects of cytokines, chemokines and growth factors in modulating corneal wound healing, cell migration, and apoptosis on the ocular surface after refractive surgery.

This prospective clinical study is going to analyze the short-term changes in ocular surface measures and tear inflammatory mediators after FLEx, LASIK and FS-LASIK procedures.

Conditions

See the medical conditions and disease areas that this research is targeting or investigating.

Myopia Astigmatism

Study Design

Understand how the trial is structured, including allocation methods, masking strategies, primary purpose, and other design elements.

Allocation Method

NON_RANDOMIZED

Intervention Model

PARALLEL

Primary Study Purpose

TREATMENT

Blinding Strategy

NONE

Study Groups

Review each arm or cohort in the study, along with the interventions and objectives associated with them.

lenticule extraction

The patients in this group chose to receive the lenticule extraction surgery.

Group Type EXPERIMENTAL

lenticule extraction

Intervention Type PROCEDURE

Four femtosecond incisions will be created in succession: the posterior surface of the refractive lenticule (spiral in), the lenticule border, the anterior surface of the refractive lenticule (spiral out), and the corneal flap in the superior region. After the suction is released, the flap will be opened using a thin, blunt spatula and the free refractive lenticule will be subsequently grasped with a forceps and extracted, after which the flap will be repositioned carefully.

laser in situ keratomileusis

The patients in this group chose to receive the laser in situ keratomileusis surgery.

Group Type EXPERIMENTAL

laser in situ keratomileusis

Intervention Type PROCEDURE

During LASIK surgery, the eye will be gently proptosed and a hinged corneal flap will be cut using a microkeratome. The flap will be lifted and the stromal bed will receive a 6 mm diameter and stroma ablation. Finally reposition the flap carefully.

FS assisted laser in situ keratomileusis

The patients in this group chose to receive the FS assisted laser in situ keratomileusis surgery.

Group Type EXPERIMENTAL

FS assisted laser in situ keratomileusis

Intervention Type PROCEDURE

Track distance and spot distance will be 3.0 μm during flap creation and 1.5 μm during flap side-cutting. The flap diameter will be 8.0 mm, and flap thickness will be set to 105 μm. Side-cut angle and hinge angle will be 90°and 50° respectively. The flaps will be created by laser scanning in spirals from the periphery to the center of the pupil. An excimer laser system will be used in the subsequent ablation of thstromal bed with a 6.0 mm optical zone. Once the excimer. ablation is completed, the flap will be repositioned in a similar fashion as in routine LASIK.

Interventions

Learn about the drugs, procedures, or behavioral strategies being tested and how they are applied within this trial.

lenticule extraction

Four femtosecond incisions will be created in succession: the posterior surface of the refractive lenticule (spiral in), the lenticule border, the anterior surface of the refractive lenticule (spiral out), and the corneal flap in the superior region. After the suction is released, the flap will be opened using a thin, blunt spatula and the free refractive lenticule will be subsequently grasped with a forceps and extracted, after which the flap will be repositioned carefully.

Intervention Type PROCEDURE

laser in situ keratomileusis

During LASIK surgery, the eye will be gently proptosed and a hinged corneal flap will be cut using a microkeratome. The flap will be lifted and the stromal bed will receive a 6 mm diameter and stroma ablation. Finally reposition the flap carefully.

Intervention Type PROCEDURE

FS assisted laser in situ keratomileusis

Track distance and spot distance will be 3.0 μm during flap creation and 1.5 μm during flap side-cutting. The flap diameter will be 8.0 mm, and flap thickness will be set to 105 μm. Side-cut angle and hinge angle will be 90°and 50° respectively. The flaps will be created by laser scanning in spirals from the periphery to the center of the pupil. An excimer laser system will be used in the subsequent ablation of thstromal bed with a 6.0 mm optical zone. Once the excimer. ablation is completed, the flap will be repositioned in a similar fashion as in routine LASIK.

Intervention Type PROCEDURE

Other Intervention Names

Discover alternative or legacy names that may be used to describe the listed interventions across different sources.

0.3% tobramycin/dexamethasone (TobraDex, Alcon) 0.5% levofloxacin (Cravit, Santen) sodium hyaluronate (HYCOSAN,URSAPHARM Arzneimittel GmbH) 0.3% tobramycin/dexamethasone (TobraDex, Alcon) 0.5% levofloxacin (Cravit, Santen) sodium hyaluronate (HYCOSAN,URSAPHARM Arzneimittel GmbH) 0.3% tobramycin/dexamethasone (TobraDex, Alcon) 0.5% levofloxacin (Cravit, Santen) sodium hyaluronate (HYCOSAN,URSAPHARM Arzneimittel GmbH)

Eligibility Criteria

Check the participation requirements, including inclusion and exclusion rules, age limits, and whether healthy volunteers are accepted.

Inclusion Criteria

* minimum age of 18 years(range from 18 year to 31 years); corneal thickness 500 μm with calculated residual stromal bed after treatment greater than 300 μm; preoperative spherical equivalent refraction between
* 2.00 diopter (D) and -6.50 D; preoperative cylindrical equivalent refraction between -0.25 D and -1.50 D; preoperative corneal curvature from 42.0 D to 46.0 D with a regular topographic pattern, verified with an Atlas topographer; monocular best corrected visual acuity of 20/20 or better and stable refractive error (less than 0.5 D change) for 24 months before surgery

Exclusion Criteria

* systemic disease that contraindicated the surgery (such as diabetes, glaucoma and systemic collagen vascular disease); corneal abnormality or disease; a history of tear supplement usage or contact lens wear during the past year
Minimum Eligible Age

18 Years

Maximum Eligible Age

31 Years

Eligible Sex

ALL

Accepts Healthy Volunteers

Yes

Sponsors

Meet the organizations funding or collaborating on the study and learn about their roles.

Sun Yat-sen University

OTHER

Sponsor Role lead

Responsible Party

Identify the individual or organization who holds primary responsibility for the study information submitted to regulators.

Xingwu Zhong, MD PhD

Professor

Responsibility Role PRINCIPAL_INVESTIGATOR

Principal Investigators

Learn about the lead researchers overseeing the trial and their institutional affiliations.

Xingwu Zhong

Role: PRINCIPAL_INVESTIGATOR

Hainan Eye Hospital, Zhongshan Ophthalmic Center of Sun Yat-sen University

Locations

Explore where the study is taking place and check the recruitment status at each participating site.

Hainan Eye Hospital, Zhongshan Ophthalmic Center of Sun Yat-sen University

Haikou, Hainan, China

Site Status

Countries

Review the countries where the study has at least one active or historical site.

China

Other Identifiers

Review additional registry numbers or institutional identifiers associated with this trial.

2015-001

Identifier Type: -

Identifier Source: org_study_id

More Related Trials

Additional clinical trials that may be relevant based on similarity analysis.

Z8 OCT-controlled 2D vs 3D LASIK
NCT04426175 COMPLETED NA
Long-term LASIK Follow up Study
NCT01695642 COMPLETED