NCT07481227

Brief Summary

Mixed astigmatism is a type of refractive error in which the two principal steep and flat meridians focus the light in front and behind the retina, respectively.1 Laser vision correction (LVC) for mixed astigmatism is challenging as it involves a bitoric ablative pattern to flatten the steepest meridian and steepen the flattest one. The aim of the current study was to compare the visual and refractive outcomes of FS-LASIK versus single-step TransPRK for treatment of patients with mixed astigmatism.

Trial Health

87
On Track

Trial Health Score

Automated assessment based on enrollment pace, timeline, and geographic reach

Enrollment
39

participants targeted

Target at P25-P50 for all trials

Timeline
Completed

Started Jun 2019

Longer than P75 for all trials

Geographic Reach
1 country

1 active site

Status
completed

Health score is calculated from publicly available data and should be used for screening purposes only.

Trial Relationships

Click on a node to explore related trials.

Study Timeline

Key milestones and dates

Study Start

First participant enrolled

June 15, 2019

Completed
6 years until next milestone

Primary Completion

Last participant's last visit for primary outcome

June 15, 2025

Completed
Same day until next milestone

Study Completion

Last participant's last visit for all outcomes

June 15, 2025

Completed
9 months until next milestone

First Submitted

Initial submission to the registry

March 15, 2026

Completed
3 days until next milestone

First Posted

Study publicly available on registry

March 18, 2026

Completed
Last Updated

March 18, 2026

Status Verified

March 1, 2026

Enrollment Period

6 years

First QC Date

March 15, 2026

Last Update Submit

March 15, 2026

Conditions

Mixed Astigmatism

Keywords

AstigmatismMixed astigmatismFS-LASIKTransPRK

Outcome Measures

Primary Outcomes (3)

  • Uncorrected distance visual acuity (UDVA)

    Visual acuity measurement using Snellen's Acuity Chart converted to logMAR notation.

    24 months

  • Corrected distance visual acuity (CDVA)

    Corrected visual acuity measurement using Snellen's Acuity Chart and converted to logMAR notation.

    24 months

  • Postoperative refraction

    Manifest sphere and cylinder measured by Topcon Auto-Keratorefractometer

    24 months

Study Arms (2)

Femtosecond laser-assisted laser in situ keratomileusis (FS-LASIK) group

Procedure: Femtosecond laser-assisted LASIK

Single-step transepithelial photorefractive keratectomy (TransPRK) group

Procedure: Single-step transepithelial PRK

Interventions

Femtosecond laser-assisted LASIKPROCEDURE

Patients in the FS-LASIK group underwent flap creation using the femtosecond laser WaveLight FS200® (Alcon lab, TX, USA). After flap creation, wave-front optimized stromal ablation was performed with WaveLight EX-500 (WaveLight®; Alcon Laboratories, Fort Worth, TX, USA) for mixed astigmatism correction.

Femtosecond laser-assisted laser in situ keratomileusis (FS-LASIK) group
Single-step transepithelial PRKPROCEDURE

Patients in the single-step TransPRK group underwent StreamLight® PRK in WaveLight EX-500 Excimer laser (WaveLight®; Alcon Laboratories, Fort Worth, TX, USA). In a single step, epithelial ablation (based on epithelial mapping) followed by stromal ablation for mixed astigmatism correction, were accomplished.

Single-step transepithelial photorefractive keratectomy (TransPRK) group

Eligibility Criteria

Age18 Years - 50 Years
Sexall
Healthy VolunteersNo
Age GroupsAdult (18-64)
Sampling MethodProbability Sample
Study Population

This was a retrospective comparative study conducted at Tiba eye center (private practice). The study reviewed and analyzed the records of patients with mixed astigmatism who underwent femtosecond laser-assisted LASIK (FS-LASIK group) or single-step TransPRK (TransPRK group) and completed 24 months of follow-up.

You may qualify if:

  • Mixed astigmatism (Plus sphere up to +4 diopters D and a minus cylinder up to -6 D).
  • Stable refraction.
  • Clear cornea.
  • Normal corneal tomography.

You may not qualify if:

  • Corrected distance visual acuity worse than 20/32 Snellen's acuity.
  • Difference between manifest and cycloplegic refraction ≥ 1 D.
  • Previous corneal or ocular surgeries, other ocular diseases.
  • Systemic diseases including diabetes mellitus and autoimmune diseases.

Contact the study team to confirm eligibility.

Sponsors & Collaborators

Study Sites (1)

TIBA Eye Center

Asyut, Asyut Governorate, 71515, Egypt

Location

Related Publications (2)

  • Kaluzny BJ, Verma S, Piotrowiak-Slupska I, Kaszuba-Modrzejewska M, Rzeszewska-Zamiara J, Stachura J, Arba-Mosquera S. Three-year outcomes of mixed astigmatism correction with single-step transepithelial photorefractive keratectomy with a large ablation zone. J Cataract Refract Surg. 2021 Apr 1;47(4):450-458. doi: 10.1097/j.jcrs.0000000000000476.

    PMID: 33252566BACKGROUND

  • Moshirfar M, Durnford K, Megerdichian A, Thomson A, Martheswaran T, West W Jr, McCabe S, Ronquillo Y, Hoopes P. Refractive Outcomes After LASIK for the Treatment of Mixed Astigmatism with the Allegretto WaveLight EX500. Ophthalmol Ther. 2022 Apr;11(2):785-795. doi: 10.1007/s40123-022-00472-4. Epub 2022 Feb 15.

    PMID: 35167040BACKGROUND

MeSH Terms

Conditions

Astigmatism

Condition Hierarchy (Ancestors)

Refractive ErrorsEye Diseases

Study Design

Study Type
observational
Observational Model
COHORT
Time Perspective
RETROSPECTIVE
Sponsor Type
OTHER
Responsible Party
PRINCIPAL INVESTIGATOR
PI Title
Professor

Study Record Dates

First Submitted

March 15, 2026

First Posted

March 18, 2026

Study Start

June 15, 2019

Primary Completion

June 15, 2025

Study Completion

June 15, 2025

Last Updated

March 18, 2026

Record last verified: 2026-03

Data Sharing

IPD Sharing
Will not share

Locations

EG(1)