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OpenTrials
Completed

NCT Number: NCT04698174

Safety and Efficacy of a New Transepithelial Photorefractive Keratectomy Treatment

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.

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Key information

Conditions

Ametropia Eye Diseases Refractive Errors

Age range

18 year–85 year

Sex eligibility

All sexes

Study type

Interventional

Phase

Not applicable

Primary location

Asian Eye Institute

Makati City, Philippines

Who can participate

Healthy volunteers accepted: No

Only the study team can determine whether someone qualifies for participation.

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

Treatment and study plan

Transepithelial Photorefractive keratectomy (tPRK) without laser polishing

Procedure

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.

Transepithelial Photorefractive keratectomy (tPRK) with laser polishing

Procedure

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.

Standard Photorefractive keratectomy (PRK)

Procedure

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.

Primary outcomes

  1. Absolute refractive predictability

    Time frame: 3 months follow up

    Absolute refractive predictability is the absolute difference between intended and achieved Manifest Refraction Spherical Equivalent (MRSE) between eyes

Secondary outcomes

  1. Monocular Uncorrected Distance Visual Acuity (UDVA) under photopic light conditions

    Time frame: 3 months follow up

    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.

  2. Monocular Uncorrected Distance Visual Acuity (UDVA) under mesopic light conditions

    Time frame: 3 months follow up

    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. Monocular Corrected Distance Visual Acuity (CDVA) under photopic light conditions

    Time frame: 3 months follow up

    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.

  4. Monocular Corrected Distance Visual Acuity (CDVA) under mesopic light conditions

    Time frame: 3 months follow up

    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.

  5. Monocular Contrast Sensitivity

    Time frame: 3 months follow up

    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.

  6. Halo Photic phenomena

    Time frame: 3 months follow up

    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).

  7. Glare Photic phenomena

    Time frame: 3 months follow up

    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).

  8. Corneal pain

    Time frame: 3 months follow up

    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.

  9. Visual perception scale

    Time frame: 3 months follow up

    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.

Other outcomes

  1. Absolute refractive predictability

    Time frame: 6 months follow up

    Absolute refractive predictability is the absolute difference between intended and achieved Manifest Refraction Spherical Equivalent (MRSE) between eyes

  2. Monocular Uncorrected Distance Visual Acuity (UDVA) under photopic light conditions

    Time frame: 6 months follow up

    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. Monocular Uncorrected Distance Visual Acuity (UDVA) under mesopic light conditions

    Time frame: 6 months follow up

    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.

  4. Monocular Corrected Distance Visual Acuity (CDVA) under photopic light conditions

    Time frame: 6 months follow up

    The visual acuity measurements will be assessed using Clinical Trial Suite (M&S Technologies, Niles, IL, USA) at 4 m, 80 cm and 40 cm in LogMAR scale under photopic light conditions. Corrected means spectacle corrected.

  5. Monocular Corrected Distance Visual Acuity (CDVA) under mesopic light conditions

    Time frame: 6 months follow up

    The visual acuity measurements will be assessed using Clinical Trial Suite (M&S Technologies, Niles, IL, USA) at 4 m, 80 cm and 40 cm in LogMAR scale under mesopic light conditions. Corrected means spectacle corrected.

  6. Halo Photic phenomena

    Time frame: 6 months follow up

    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).

  7. Glare Photic phenomena

    Time frame: 6 months follow up

    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).

  8. Corneal pain

    Time frame: 6 months follow up

    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. Higher scores indicate higher level of pain, where 0 is 'None' and 10 is the highest level of 'Severe'. Higher scores indicate higher level of pain.

  9. Visual perception scale

    Time frame: 6 months follow up

    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.

Sponsors and collaborators

Lead sponsor

Bausch & Lomb Incorporated

Industry

Registry information

Official study title

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

Important dates

Study start
2021
Primary completion
2022
Study completion
2022
First posted
Jan 6, 2021
Registry last updated
Oct 7, 2022

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

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