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Completed

NCT Number: NCT05733741

Preservative-free Topical Anesthetics for Post-PRK Pain

The goal of this interventional comparative study is to assess the efficacy and safety of a novel regimen of preservative-free unit-dose topical anesthetics for controlling early postoperative pain following single-step transepithelial PRK surgery.

The main research questions to answer are:

* Question 1: Are topical anesthetics effective in reducing post-PRK pain? * Question 2: Are short-term topical anesthetics toxic to the cornea? * Question 3: How to prevent abuse of topical anesthetics by patients at home?

Participants were planned to undergo a bilateral single-step transepithelial PRK surgery to correct their refractive errors and received a standard post-PRK treatment regimen for both eyes. Additionally, one eye was offered a preservative-free topical anesthetic as an experimental group and the other eye was offered a preservative-free artificial tear as a control group.

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Key information

Conditions

Myopia Eye Diseases Refractive Errors

Age range

18 year and older

Sex eligibility

All sexes

Study type

Interventional

Phase

Phase 4

Primary location

Tiba Eye Center

Asyut, 71516, Egypt

About this study

Photorefractive keratectomy (PRK) is a well-established surface ablation procedure for correction of refractive errors which involves the removal of corneal epithelium in a large diameter usually more than 6 mm followed by stromal ablation.

Early postoperative pain within the first few days after surgery is one of the commonest complications reported after PRK. The classic postoperative treatment includes the prescription of topical antibiotics and frequent preservative-free lubricants to accelerate epithelial healing.

The current treatment regimens also includes topical steroids, topical non-steroidal anti-inflammatory drugs (NSAID) and oral NSAID to reduce inflammation and post-PRK pain.

Earlier studies suggested that topical anesthetics in diluted concentrations and fractional doses didn't delay corneal epithelial regeneration after PRK but their use didn't gain popularity because of problems with topical formulation, stability and preservation.

Who can participate

Healthy volunteers accepted: Yes

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

Inclusion criteria

Patients who are candidate for PRK surgery with

  • Myopia up to - 6 diopters or myopic astigmatism up to - 4 diopters.
  • Corneal thinnest pachymetry of 500 µm
  • Residual stromal bed more than 350 µm after epithelial ablation.

Exclusion criteria

Patients with

  • Corneal scars or dry eye disease,
  • Past ocular surgery,
  • History of contact lens wear,
  • Systemic diseases such as diabetes mellitus and autoimmune diseases,
  • History of oral analgesics abuse.

Treatment and study plan

Preservative-free Benoxinate hydrochloride 0.4% (Benoxidia unit-dose vials [UD], Orchidia pharmaceutical Ind., Egypt)

Drug

For each patient, one eye was treated with preservative-free Benoxinate hydrochloride 0.4%.

The prescribed regimen comprises of the instillation of one drop immediately, 2, 4, 6 and 8 hours after the end of surgery.

Every patient was given 5 UD vials only of preservative-free Benoxinate hydrochloride 0.4% at each follow up visit for the next postoperative day usage administered 5 times daily (every 3 hours while awake) for the first 3 postoperative days giving clear instructions to immediately discard the vial after single use.

Preservative-free Sodium hyaluronate 0.2% (Polyfresh unit-dose vials [UD], Orchidia pharmaceutical Ind., Egypt).

Drug

The other eye was treated with preservative-free Sodium hyaluronate 0.2%. The prescribed regimen comprises of the instillation of one drop immediately, 2, 4, 6 and 8 hours after the end of surgery.

Every patient was given 5 UD vials only of preservative-free Sodium hyaluronate 0.2% at each follow up visit for the next postoperative day usage administered 5 times daily (every 3 hours while awake) for the first 3 postoperative days giving clear instructions to immediately discard the vial after single use.

Primary outcomes

  1. Postoperative pain score on the verbal rating scale (VRS)

    Time frame: 1 week

    The doctor asks the patient to choose the word that best describes his/her pain and then gives it a score from zero to 4 (Zero for no pain, 1 for mild pain, 2 for moderate pain, 3 for severe pain and 4 for unbearable pain).

  2. Postoperative pain score on the visual analogue scale (VAS)

    Time frame: 1 week

    The patient is asked to rate his/her pain by choosing a number on a scale from zero to 10 considering zero as no pain and 10 as worst possible pain.

Secondary outcomes

  1. Corneal epithelial healing duration

    Time frame: 1 week

    Time for the corneal epithelium to heal reported in days after PRK surgery

  2. Endothelial cell density (ECD)

    Time frame: from preoperative to 1 month postoperative.

    Specular microscopy was used to assess endothelial cell count before and after PRK surgery

Sponsors and collaborators

Lead sponsor

Assiut University

Other

Registry information

Official study title

Preservative-free Topical Anesthetics for the Management of Postoperative Pain Following Photorefractive Keratectomy

Important dates

Study start
2023
Primary completion
2023
Study completion
2023
First posted
Feb 17, 2023
Registry last updated
May 24, 2023

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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