Photorefractive Keratectomy (PRK) : Comparison of Corneal Haze Between Two Modes of De-epithelialisation (Laser Versus Manual Alcohol)

NCT ID: NCT05072977

Last Updated: 2025-12-08

Basic Information

• Recruitment Status: TERMINATED
• Clinical Phase: NA
• Total Enrollment: 71 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2022-02-09
• Study Completion Date: 2024-07-10

Brief Summary

surgical correction of ametropia. A number of improvements have been introduced to overcome the side effects and complications such as corneal haze, epithelial irregularities induced by wound healing, pain and delayed visual acuity recovery associated with PRK surgery. During traditional PRK, the corneal epithelium is mechanically debrided before stromal ablation is performed. Alcohol PRK is frequently used as an alternative to mechanical epithelial debridement and is considered simpler and faster. Transepithelial PRK (TransPRK) is a new method in which the corneal epithelium is photoablated by the laser in one step using a specific ablation profile.

This study attempts to establish a means of quantitatively and objectively measuring corneal haze, using patented software based on optical coherence tomography (OCT) of the cornea. This will confirm or refute the hypothesis of a lower occurrence of corneal haze after TransPRK (experimental group) versus PRK with alcohol (control group). Each patient will have one eye randomised to one of the two groups being compared.

Conditions

Myopia; Astigmatism

Study Design

• Allocation Method: RANDOMIZED
• Intervention Model: PARALLEL
• Primary Study Purpose: TREATMENT
• Blinding Strategy: SINGLE

Study Groups

TransPRK

Group Type: EXPERIMENTAL

TransPRK

Intervention Type: PROCEDURE

A Merocel sponge is soaked in a saline solution to expand before being gently applied to the corneal surface in three gestures similar to painting. This standardised procedure avoids inhomogeneous wetting of the cornea, which would result in uneven ablation. The laser ablation is then performed.

Alcohol PRK

Group Type: ACTIVE_COMPARATOR

Alcohol PRK

Intervention Type: PROCEDURE

A ring is placed in the centre of the cornea and filled with 20% alcohol. After 20 seconds of exposure, the alcohol is absorbed with a small sponge and the corneal epithelium is debrided with a polyvinyl alcohol expanding sponge (Merocel, Medtronic). The entire cornea is rinsed with balanced salt solution and the epithelium is peeled away from the corneal stroma. The corneal bed is then dried with a small sponge and laser ablation is performed.

Interventions

TransPRK

A Merocel sponge is soaked in a saline solution to expand before being gently applied to the corneal surface in three gestures similar to painting. This standardised procedure avoids inhomogeneous wetting of the cornea, which would result in uneven ablation. The laser ablation is then performed.

Intervention Type: PROCEDURE

Alcohol PRK

A ring is placed in the centre of the cornea and filled with 20% alcohol. After 20 seconds of exposure, the alcohol is absorbed with a small sponge and the corneal epithelium is debrided with a polyvinyl alcohol expanding sponge (Merocel, Medtronic). The entire cornea is rinsed with balanced salt solution and the epithelium is peeled away from the corneal stroma. The corneal bed is then dried with a small sponge and laser ablation is performed.

Intervention Type: PROCEDURE

Eligibility Criteria

Inclusion Criteria

• Planned Photorefractive Keratectomy in both eyes
• Simple myopia or myopic astigmatism, refractive spherical equivalent between -0.50 and -9.0 diopters in both eyes with regular corneal topography

Exclusion Criteria

• Only one eye operated on
• At least one contraindication to refractive surgery, namely : keratoconus, minimum corneal thickness < 400 µm, severe dry syndrome, progressive corneal infection
• Personal history of corneal surgery
• Personal history of ocular pathology other than simple myopia or myopic astigmatism
• Pregnant or breastfeeding woman

• Minimum Eligible Age: 18 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: No

Sponsors

Fondation Ophtalmologique Adolphe de Rothschild

NETWORK

Sponsor Role: lead

Responsible Party

Responsibility Role: SPONSOR

Principal Investigators

Alain SAAD, MD

Role: PRINCIPAL_INVESTIGATOR

Hôpital Fondation A. de Rothschild

Locations

Hôpital Fondation A. de Rothschuld

Paris, , France

Countries

France

Other Identifiers

ASD_2021_8

Identifier Type: -

Identifier Source: org_study_id