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

NCT07203976 | Active Not Recruiting

• 1 other identifier: 04-2025-300627
• Study Type: observational
• Target: 100
• Locations: 1 country
• Sites: 1

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.

Conditions

Photorefractive Keratectomy

Keywords

stream light photorefractive keratectomy; conventional photorefractive keratectomy

Outcome Measures

Primary Outcomes (1)

• Post operative distant uncorrected visual acuity

  using snellen chart

  1 year

Secondary Outcomes (1)

• Post operative spherical equivalent of refractive error

  1 year

Study Arms (2)

Patients aged 18-40 years, myopia up to -6.00 D and astigmatism up to -3.00 D and Stable refraction

The visual and refractive outcomes of Stream Light Photorefractive keratectomy with fixed epithelial removal.

Patients aged 18-40 years, myopia up to -6.00 D and astigmatism up to -3.00 D and Stable refraction

The visual and refractive outcomes of manual Photorefractive keratectomy with fixed epithelial removal.

Eligibility Criteria

• Age: 18 Years - 40 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64)
• Sampling Method: Probability Sample

Study Population

Patients aged 18-40 years with myopia up to -6.00 D and astigmatism up to -3.00 D and Stable refraction for at least one year.

You may qualify if:

• 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.

You may not qualify if:

• 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.

Sponsors & Collaborators

• Assiut University: lead

Study Sites (1)

Faculty of medicine, Assiut

Asyut, Egypt

Location

Related Publications (2)

• 3. Marshall, J., Trokel, S. L., Rothery, S., & Krueger, R. R. (2018). Refractive corneal surgery: The role of epithelial healing and biomechanics. Cornea, 37(7), 853-860.

  BACKGROUND

• Fantes FE, Hanna KD, Waring GO 3rd, Pouliquen Y, Thompson KP, Savoldelli M. Wound healing after excimer laser keratomileusis (photorefractive keratectomy) in monkeys. Arch Ophthalmol. 1990 May;108(5):665-75. doi: 10.1001/archopht.1990.01070070051034.

  PMID: 2334323 BACKGROUND

Study Design

• Study Type: observational
• Observational Model: OTHER
• Time Perspective: RETROSPECTIVE
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: lecturer of ophthalmology

Study Record Dates

• First Submitted: September 24, 2025
• First Posted: October 2, 2025
• Study Start: May 3, 2025
• Primary Completion: February 1, 2026
• Study Completion: May 1, 2026
• Last Updated: October 2, 2025

Record last verified: 2025-09

Locations

EG (1)