Comparison Between Bare Scleral Technique and Conjunctival Auto-graft on Corneal Topography After Pterygium Surgery

Study Overview
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Brief Summary
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Aim of the work: To study the corneal topographic pattern changes in patients who have pterygium excision by two surgical techniques (bare sclera, conjunctival autograft).

Detailed Description
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Pterygium is one of the common ocular surface disorders , it's is an elastotic triangular fibro-vascular tissue covered by conjunctival epithelium that spreads over the cornea. Pterygium causes differences in curvature & power across the cornea . The prevalence of pterygium varies from 1.1% to 53% globally in different environmental conditions. Risk factors include;UV radiation, geographical latitude near to the equator, outdoor activity , aging, male, and dusty environment. Pterygium excision is important in patients suffering from blurred vision due to astigmatism . Surgical techniques include ; bare sclera excision, conjunctival autograft, conjunctival transpositional flap, and amniotic membrane grafting. Pterygium excision increases in the mean central corneal curvature & reduces astigmatism that leads to improvement in visual acuity. Corneal topography is a gold standard in corneal pathology follow-up. Corneal topography is a computer assisted diagnostic tool that creates a three-dimensional map of the surface curvature of the cornea. Corneal topography produces a detailed, visual description of the shape and power of the cornea. In this study , corneal topography is used to detect how does corneal curvature change after excision of pterygium .

Official Title
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A Comparative Study Between Bare Scleral Technique and Conjunctival Autograft on Corneal Topography After Pterygium Surgery

Conditions
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Corneal Topography

Intervention / Treatment
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* Device: corneal topography


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria:- Patients with pterygium not associated with other pathologies (suitable for excision). Nasal pterygium extended to the cornea. Exclusion Criteria: - Associated pathologies such as glaucoma, and cataract. Corneal opacities or irregularities, scars, dystrophy or ectasia. Patients who underwent previous corneal surgery (including refractive surgery) Pseudo-pterygium.
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 |
| --- | --- |
| pterygium surgery with bare scleral technique<br>corneal topograghy before and after surgery | Device: corneal topography<br>* corneal topography before and after pterygium surgery by two techniques bare scleral and conjunctival autograft<br>|
| pterygium surgery with conjunctival autograft technique<br>corneal topograghy before and after surgery | Device: corneal topography<br>* corneal topography before and after pterygium surgery by two techniques bare scleral and conjunctival autograft<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| comparison of topography finding after pterygium surgery by the bare scleral technique. | To investigate the corneal topographic changes by imaging the corneal topography before and after pterygium excision (by the bare scleral technique); to detect corneal curvature changes. | baseline | 
| comparison of topography finding after pterygium surgery by the conjunctival auto-graft technique. | To investigate the corneal topographic changes by imaging the corneal topography before and after pterygium excision (by the conjunctival auto-graft technique); to detect corneal curvature changes. | baseline | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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pterygium surgery by bare scleral & autograft