Safety and Efficacy of a New Transepithelial Photorefractive Keratectomy Treatment

Study Overview
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Brief Summary
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This is a prospective, comparative, randomized, controlled, single-blind, single-surgeon, single-center PMCF clinical study whereby participants undergoing refractive surgery for correction of ametropia will receive a transepithelial PRK (tPRK) and conventional PRK treatment in the contralateral eye. To avoid bias in the clinical outcomes, the two PRK treatment options are randomized to the eyes of the patients based on ocular dominance. In addition, a 1:1 randomization is applied within the tPRK group to eyes with and without end-treatment laser polishing. Both procedures, standard PRK and tPRK, are performed in a one-step procedure. The main difference between the procedures is, that in conventional PRK, the epithelium will be removed using alcohol, whereas in tPRK procedures, the epithelium will be removed by laser ablation.

Official Title
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Prospective Clinical Study to Evaluate the Safety and Efficacy of a New Transepithelial Photorefractive Keratectomy Treatment

Conditions
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Ametropia

Intervention / Treatment
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* Procedure: Transepithelial Photorefractive keratectomy (tPRK) without laser polishing
* Procedure: Transepithelial Photorefractive keratectomy (tPRK) with laser polishing
* Procedure: Standard Photorefractive keratectomy (PRK)


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Ametropia Myopic subjects with refractive spherical equivalent (MRSE) between -1.5D and -9.0D Hyperopic subjects with refractive spherical equivalent (MRSE) between +1.5D and +5.25D Signed informed consent form Exclusion Criteria: Ocular comorbidity Subject taking systemic medications likely to affect wound healing such as corticosteroids or antimetabolites. Subjects who are known to be pregnant, lactating, or who plans to become pregnant over the medications used for standard tPRK. Subjects participating in any other ophthalmic clinical trial during this clinical study. Subjects with cognitive impairments or other vulnerable persons

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 85 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Transepithelial Photorefractive keratectomy (tPRK) without laser polishing<br> | Procedure: Transepithelial Photorefractive keratectomy (tPRK) without laser polishing<br>* Transepithelial Photorefractive keratectomy (tPRK) with laser ablation of the corneal epithelium and stroma in a single-step procedure using the B+L Teneo 317 Model 2 Excimer Laser.<br>|
| Experimental: Transepithelial Photorefractive keratectomy (tPRK) with laser polishing<br> | Procedure: Transepithelial Photorefractive keratectomy (tPRK) with laser polishing<br>* Transepithelial Photorefractive keratectomy (tPRK) using the B+L Teneo 317 Model 2 Excimer Laser with end-treatment laser polishing using a fixed thickness of the additional layer of 5 μm.<br>|
| Active Comparator: Standard Photorefractive keratectomy (PRK)<br> | Procedure: Standard Photorefractive keratectomy (PRK)<br>* Conventional Photorefractive keratectomy (PRK) with alcohol-assisted epithelium ablation. Then the aspheric ablation profile will be performed using the B+L Teneo 317 Model 2 Excimer Laser.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Absolute refractive predictability | Absolute refractive predictability is the absolute difference between intended and achieved Manifest Refraction Spherical Equivalent (MRSE) between eyes | 3 months follow up | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Monocular Uncorrected Distance Visual Acuity (UDVA) under photopic light conditions | The visual acuity measurements will be assessed using Clinical Trial Suite (M&S Technologies, Niles, IL, USA) at 4 m in LogMAR scale under photopic light conditions. | 3 months follow up | 
| Monocular Uncorrected Distance Visual Acuity (UDVA) under mesopic light conditions | The visual acuity measurements will be assessed using Clinical Trial Suite (M&S Technologies, Niles, IL, USA) at 4 m in LogMAR scale under mesopic light conditions. | 3 months follow up | 
| Monocular Corrected Distance Visual Acuity (CDVA) under photopic light conditions | The visual acuity measurements will be assessed using Clinical Trial Suite (M&S Technologies, Niles, IL, USA) at 4 m in LogMAR scale under photopic light conditions. Corrected means spectacle corrected. | 3 months follow up | 
| Monocular Corrected Distance Visual Acuity (CDVA) under mesopic light conditions | The visual acuity measurements will be assessed using Clinical Trial Suite (M&S Technologies, Niles, IL, USA) at 4 m in LogMAR scale under mesopic light conditions. Corrected means spectacle corrected. | 3 months follow up | 
| Monocular Contrast Sensitivity | The contrast sensitivity test consists in assessing the possibility to distinguish the alternation of white and grey fringes of difference contrast with difference frequency. Contrast sensitivity will be assessed under photopic and mesopic light conditions using Clinical Trial Suite (M&S Technologies, Niles, IL, USA) device at 2.5 m. | 3 months follow up | 
| Halo Photic phenomena | The amount and disturbance of photic halo side effects will be assessed by the Halo Simulator: With this software tool the particant mimics the individual vision perception by adjusting a typical night scene image with the intensity and size of halo. The simulator utilizes a numerical scale to quantify the size and intensity of halos, ranging from 0 (none), 25 (mild), 50 (moderate), 75 (severe) to 100 (very severe). | 3 months follow up | 
| Glare Photic phenomena | The amount and disturbance of photic glare side effects will be assessed by the Glare simulator: With this software tool the particant mimics the individual vision perception by adjusting a typical night scene image with the intensity and size of glare. The simulator utilizes a numerical scale to quantify the size and intensity of glare, ranging from 0 (none), 25 (mild), 50 (moderate), 75 (severe) to 100 (very severe). | 3 months follow up | 
| Corneal pain | The epithelial healing process after photorefractive keratectomy treatment often comes along with the perception of some corneal pain. To assess the pain level, the participants will receive a self-administered pain questionnaire to fill out every day from the day of the surgery until they return for the 6-9 days follow up visit. An 11-point scale will be used to rate the self-reporting of pain, where 0 is 'None' and 10 is the highest level of 'Severe'. Higher scores indicate higher level of pain. | 3 months follow up | 
| Visual perception scale | To assess the visual perception level, the participants will receive a self-administered visual perception questionnaire to fill out every day from the day of the surgery until they return for the 6-9 days follow up visit. A 4-point scale will be used to rate the self-reporting of visual perception, with 1 = 'Clear' and 4 = 'Very Poor' vision. Higher scores indicate poorer visual perception. | 3 months follow up |