Preservative-free Topical Anesthetics for Post-PRK Pain
Study Details
Study Description
Brief Summary
The goal of this interventional comparative study is to assess the efficacy and safety of a novel regimen of preservative-free topical anesthetics for controlling early postoperative pain following single-step transepithelial PRK surgery.
The main questions it aims to answer are:
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Question 1: Are topical anesthetics effective in reducing post-PRK pain?
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Question 2: Do topical anesthetics inversely affect the epithelial healing duration? Participants will undergo a bilateral single-step transepithelial PRK surgery to correct their refractive errors and will receive a standard post-PRK treatment regimen for both eyes. Additionally, one eye will be offered a preservative-free topical anesthetic as an experimental group and the other eye will be offered a preservative-free artificial tear as a control placebo group.
| Condition or Disease | Intervention/Treatment | Phase |
|---|---|---|
|
Phase 4 |
Detailed Description
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.
Study Design
Arms and Interventions
| Arm | Intervention/Treatment |
|---|---|
| Experimental: Preservative-free topical anesthetics group Patients in this group will have the standard post-PRK treatment regimen in addition to the prescription of preservative-free topical anesthetics for pain control following single-step transepithelial PRK surgery in one eye. |
Drug: Preservative-free Benoxinate hydrochloride 0.4% (Benoxidia unit-dose vials [UD], Orchidia pharmaceutical Ind., Egypt)
For each patient, one eye was treated with preservative-free Benoxinate hydrochloride 0.4%.
The prescribed regimen comprises the instillation of one drop immediately, 3 and 6 hours after the end of surgery.
Every patient was given 3 UD vials only of each type at each follow up visit for the next postoperative day usage administered 3 times daily (one UD vial in the early morning, one in the afternoon and one UD vial at night) for the first 3 postoperative days giving clear instructions to immediately discard the vial after single use.
|
| Placebo Comparator: Preservative-free artificial tears group Patients in this group will have the standard post-PRK treatment regimen in addition to the prescription of preservative-free artificial tears as a placebo following single-step transepithelial PRK surgery in the other eye. |
Drug: Preservative-free Sodium hyaluronate 0.2% (Polyfresh unit-dose vials [UD], Orchidia pharmaceutical Ind., Egypt).
The other eye was treated with preservative-free Sodium hyaluronate 0.2%. The prescribed regimen comprises the instillation of one drop immediately, 3 and 6 hours after the end of surgery.
Every patient was given 3 UD vials only of each type at each follow up visit for the next postoperative day usage administered 3 times daily (one UD vial in the early morning, one in the afternoon and one UD vial at night) for the first 3 postoperative days giving clear instructions to immediately discard the vial after single use.
|
Outcome Measures
Primary Outcome Measures
- Postoperative pain score on the verbal rating scale (VRS) [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).
- Postoperative pain score on the visual analogue scale (VAS) [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 Outcome Measures
- Corneal epithelial healing duration [1 week]
Time for the corneal epithelium to heal reported in days after PRK surgery
Eligibility Criteria
Criteria
Inclusion Criteria:
Patients who are candidate for PRK surgery with
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Myopia up to - 6 diopters or myopic astigmatism up to - 4 diopters.
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Corneal thinnest pachymetry of 500 µm
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Residual stromal bed more than 350 µm after epithelial ablation.
Exclusion Criteria:
Patients with
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Corneal scars or dry eye disease,
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Past ocular surgery,
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History of contact lens wear,
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Systemic diseases such as diabetes mellitus and autoimmune diseases,
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History of oral analgesics abuse.
Contacts and Locations
Locations
| Site | City | State | Country | Postal Code | |
|---|---|---|---|---|---|
| 1 | Tiba Eye Center | Assiut | Egypt | 71516 |
Sponsors and Collaborators
- Assiut University
Investigators
- Principal Investigator: Mahmoud Abdel-Radi, MD, Assiut University
Study Documents (Full-Text)
None provided.More Information
Publications
- PFTAPRK