Effect of Ectoine After Photorefractive Keratectomy (PRK).

Study Overview
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Brief Summary
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This is a comparative, open label, parallel group, non interventional study aims to assess the effect of Ectoine containing eye drops on stromal haze, pain and epithelial healing after Photorefractive keratectomy (PRK). The patient apply Ectohylo eye drops (Ectoine +Sodium Hyauronate) in the right eye and Polyfresh Extra eye drops (Carboxymethyl cellulose + Sodium Hyauronate ) in the left eye plus the routine post PRK treatment in both eyes. Post operative pain , epithelial healing and corneal densitometry is observed in both eyes.

Detailed Description
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Photorefractive keratectomy (PRK) is a commonly used operation for laser vision correction. The main fears of this type of laser vision correction is corneal haze, delayed epithelial healing and postoperative severe pain. Ectoine is a natural compound that has the ability to protect biological membranes from damage and environmental effects. This study assess the use of Ectoine containing eye drops to protect the bare ocular surface and reduce inflammation after PRK that will inturn is expected to affect the post operative corneal haze, pain, and epithelial healing .

Official Title
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Effect of Ectoine on Stromal Haze, Wound Healing and Pain After Photorefractive Keratectomy.

Conditions
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Photorefractive Keratectomy, Corneal Haze

Intervention / Treatment
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* Other: Ectohylo (R) eye drops


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patient undergoing PRK for myopia and myopic astigmatism when astigmatism is 2.5 diopters or less and myopia with spherical equivalent -4 or less. Exclusion Criteria: patient spherical equivalent more myopic than -4 diopters Patients with astigmatism more than 2.5 diopter Patients with anisometropia ( difference > 2 diopters) Patient with previous ocular surgery Patients with chronic systemic disease that can affect results of laser vision correction (e.g. rheumatoid arthritis) Pregnant and lactating females

Ages Eligible for Study
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Minimum Age: 19 Years
Maximum Age: 35 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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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Ectoine Eye<br>The right eye of the studied group will be given 2% Ectoine containig , 0.2% sodium hyaluronate eye drops(Ectohylo) hourly. | Other: Ectohylo (R) eye drops<br>* using Ectohylo eye drops post operative after PRK in the right eyes of the patients<br>* Other names: Ectoine 2% eye drops;|
| Control eye<br>The left eye of the studied group will be give Carboxymethyl cellulose, 0.2% sodium hyaluronate eye drops(Polyfresh Extra) hourly. | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Corneal Densitometry (assesed by Pentacam). | Post photo refractive keratectomy early haze (3 months after operation) assesed by Pentacam densitometry | 3 months post operative | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Pain score (0 -10) | pain in the first 2 days post operative (graded 0 to 10) | 2 days | 
| Time of Epithelial healing (days) | Time required for epithelial healing after PRK in days | 2-7 days | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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PRK, surface ablation, corneal haze