Visual and Refractive Outcomes Following Stream Light Photorefractive Keratectomy (55μm Epithelial Removal) Versus Conventional Photorefractive Keratectomy

Status

Active, not recruiting

Phases

Unknown

Study type

Observational

Source

ClinicalTrials.gov

Registry ID

NCT07203976

Enrollment

100

Registered

2025-10-02

Start date

2025-05-03

Completion date

2026-05-31

Last updated

2025-10-02

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Photorefractive Keratectomy

Keywords

stream light photorefractive keratectomy, conventional photorefractive keratectomy

Brief summary

Photorefractive keratectomy (PRK) is a well-established corneal refractive surgery that involves epithelial removal followed by stromal ablation to correct myopia, hyperopia, and astigmatism. The method of epithelial removal in PRK significantly impacts healing, pain levels, and visual outcomes. Trans-epithelial PRK (StreamLight) performed on the EX500 excimer laser platform removes the epithelium and reshapes the corneal stroma in a single laser-guided step, potentially reducing tissue manipulation and enhancing epithelial healing. In contrast, manual epithelial removal PRK involves mechanical debridement, with epithelial removal depth being manually controlled. The variability of epithelial thickness in StreamLight PRK may influence visual outcomes, whereas in manual PRK, a fixed epithelial removal depth of 55 microns provides a standardized approach.

Detailed description

This study aimed to compare the visual and refractive outcomes of StreamLight PRK versus manual PRK with fixed epithelial removal. Type of the study: Retrospective cross-sectional study * Study Setting: Alforsan Eye Centre * Study subjects: a. Inclusion criteria: * Patients aged 18-40 years. * Myopia up to -6.00 D and astigmatism up to -3.00 D. * Stable refraction for at least one year. * No history of ocular surgery or corneal pathology. b. Exclusion criteria: * Presence of keratoconus or suspected corneal ectasia. * Severe dry eye disease or significant ocular surface disease. * History of autoimmune disease or systemic conditions affecting wound healing. * Prior herpetic eye disease. c. Sample Size Calculation: A sample size calculation will be performed to ensure adequate statistical power. Anticipated enrollment: \[e.g., 50 eyes per group\] based on previous PRK outcome studies (Marshall et al., 2018). * Study tools (in detail, e.g., lab methods, instruments,steps, chemicals, …): * Alcon Wavelight EX500 excimer laser (Alcon Laboratories, Fort Worth, TX, USA) * Wavelight Oculyzer II Am Wolfsmantel 5, Erlangen, Germany * Autorefractor KR-8900 (Topcon, Tokyo, Japan)

Interventions

None listed

Study design

Observational model

OTHER

Time perspective

RETROSPECTIVE

Eligibility

Sex/Gender

ALL

Age

18 Years to 40 Years

Healthy volunteers

Inclusion criteria

* Patients aged 18-40 years. * Myopia up to -6.00 D and astigmatism up to -3.00 D. * Stable refraction for at least one year. * No history of ocular surgery or corneal pathology.

Exclusion criteria

* Presence of keratoconus or suspected corneal ectasia. * Severe dry eye disease or significant ocular surface disease. * History of autoimmune disease or systemic conditions affecting wound healing. * Prior herpetic eye disease.

Design outcomes

Primary

Measure	Time frame	Description
Post operative distant uncorrected visual acuity	1 year	using snellen chart

Secondary

Measure	Time frame	Description
Post operative spherical equivalent of refractive error	1 year	using autorefractometer

Countries

Egypt

Outcome results