Contribution of SA and Coma to The Total Ocular HOA Before and After FS-LASIK Using An Aspheric Ablation Profile

Not Applicable

• Conditions: FS-LASIK Surgery Effect on Higher Order Aberrations
• Interventions: Procedure: LASIK refractive surgery

• Registration Number: NCT04966806
• Lead Sponsor: Kasr El Aini Hospital

Brief Summary

Laser-assisted in situ keratomileusis (LASIK) is the most frequently performed refractive surgery procedure for the correction of myopia, hyperopia, and astigmatism.

There is a continuous upgrade and development in LVC surgeries correlated with the evolution of new machines and enhancement of the ablation profiles. One of the main undesirable effects of corneal refractive surgeries using conventional ablation profiles is the increase in HOAs which is associated with haloes, glare, ghost images, starburst patterns and monocular diplopia, especially in low lighting conditions and during night driving.

Over the years many ablation profiles have been developed such as wavefront-guided, wavefront optimized, topography guided, Q- Value based and aspheric ablation profiles. These profiles aim to abolish LOAs and to prevent induction or increase of pre-existing HOAs aiming to improve the quality of vision experienced post-operative.

In spite of the vast body of research in this area, there remains a gap in the literature investigating higher-order aberrations' components in-depth. Therefore, this study aims to investigate the contribution of spherical aberration and coma to the total higher order aberration before and after femtosecond assisted laser in situ keratomileusis using an aspheric ablation profile.

This current study is a Descriptive analytical study that was conducted on 34 eyes of 17 patients who underwent corneal refractive surgery.

The results were analyzed to compare the effect of FS-LASIK surgery on corneal coma and SA, and the contribution of each of them on total ocular HOAs preoperative and post-operative.

Detailed Description

Not available

Study Timeline

• Study First Submitted: 2021-06-25
• Status Verified: 2021-07
• Study Start: 2021-07-10
• Study First Submitted QC: 2021-07-14
• Last Update Submitted: 2021-07-14
• Study First Posted: 2021-07-19
• Last Update Posted: 2021-07-19
• Primary Completion: 2021-10-15
• Study Completion: 2021-12-15

Recruitment & Eligibility

• Status: UNKNOWN
• Sex: All
• Target Recruitment: 17

Inclusion Criteria

1. Age: between 18 years and 45 years
2. Myopes from -1.50 D to -8.00 D
3. Astigmatism less than -4.00 D
4. Normal Corneal Tomography with a Belin Ambrosio big D value of less than 1.6

Exclusion Criteria

1. Unstable refraction for 1 year
2. Corneal thickness less than 500 microns
3. Expected Post Lasik Residual Stromal bed less than 300 microns
4. All patients with post operative complications as epithelial overgrowth or decentered ablation.

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: SINGLE_GROUP

Arm && Interventions

Group	Intervention	Description
Percentage of Coma and SA to Total ocular HOA	LASIK refractive surgery	-

Primary Outcome Measures

Name	Time	Method
Change in percentage of contribution of coma and spherical aberration from total ocular HOA before and after FS-LASIK.	6 months	Measuring unit for coma and spherical aberrations and total ocular HOA is equivalent Diopters.; The contribution of coma and spherical aberrations to total ocular HOA will be measured as a percentage.

Trial Locations

Locations (1)

Kasr Al Ainy; 🇪🇬 Cairo, Egypt