Evaluation of Corneal Irregular Astigmatism and Visual Quality Following Bilateral Sequential Small Incision Lenticule Extraction (SMILE) and Laser Subepithelial Keratomileusis (LASEK): A Six-Year Comparative Study

Completed

• Conditions: Myopia

• Registration Number: NCT06673992
• Lead Sponsor: Shanghai 10th People's Hospital

Brief Summary

To compare the corneal spherical component (SC), regular astigmatism (RA), irregular astigmatism (IA, including Asymmetry and Irregularity) and visual quality six years after small incision lenticule extraction (SMILE) and laser subepithelial keratomileusis (LASEK) for mild to moderate myopia.

Detailed Description

Not available

Study Timeline

• Study Start: 2017-10-01
• Primary Completion: 2024-05-30
• Study Completion: 2024-10-01
• Study First Submitted: 2024-10-26
• Status Verified: 2024-11
• Study First Submitted QC: 2024-11-02
• Last Update Submitted: 2024-11-02
• Study First Posted: 2024-11-05
• Last Update Posted: 2024-11-05

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 71

Inclusion Criteria

• (1) patients aged over 18 years; (2) absence of corneal, ocular, or systemic diseases; (3) stable refractive diopter maintained for the past 2 years with a change of ± 0.50 diopter; (4) discontinuation of soft contact lens wear for at least 2 weeks and rigid contact lenses for at least 4 weeks prior to surgery; (5) preoperative manifest refraction spherical equivalent (MRSE) less than -6.00 diopter (D)

Exclusion Criteria

A history of moderate to severe dry eye as well as any ocular or systemic disease that would contraindicate laser refractive surgery

Study & Design

• Study Type: OBSERVATIONAL
• Study Design: Not specified

Primary Outcome Measures

Name	Time	Method
Corneal Irregular Astigmatism	preoperative and 6 years postoperatively	The swept-source anterior segment OCT (CASIA SS-1000) was utilized to acquire corneal topography measurements. In the Corneal Map mode, 16 radial cross-sectional images (512 telecentric+A-scans) were obtained within a duration of 0.3 s for each measurement. The analysis program identified and digitized the anterior and posterior corneal surfaces to evaluate distributions of corneal power and corneal height for both the anterior and posterior corneal surfaces. The unit of Corneal Irregular Astigmatism is D.
wavefront aberration	preoperative and 6 years postoperatively	The wavefront aberrations were measured and analyzed for 6-mm pupil diameter with a Zywave aberrometer using a Hartmann-Shack sensor (Bausch \& Lomb, US). The absolute Zernike coefficients including vertical trefoil, horizontal trefoil, vertical coma, horizontal coma, spherical aberration, and total higher-order aberrations (tHOAs) were examined. The unit of wavefront aberration is um.

Trial Locations

Locations (1)

Shanghai 10th People's Hospital; 🇨🇳 Shanghai, China