Visual Outcomes of Topography Guided Photorefractive Keratectomy (PRK) for Treatment of Patients With Irregular Cornea

Not Applicable

Completed

• Conditions: Irregular Astigmatism
• Interventions: Procedure: photorefractive keratectomy (PRK)

• Registration Number: NCT03140046
• Lead Sponsor: Assiut University

Brief Summary

Irregular astigmatism is one of the most serious and frequent complications of corneal refractive surgery and one of the worst sequelae of other forms of corneal surgery . It is also considered as one of common, serious complications of corneal injuries .

Spectacle correction is usually not useful in the correction of corneal irregular astigmatism. Contact lenses represent a good alternative, but their adaptation and stability are limited by the irregular corneal surface and patient discomfort.

In recent years, advancements in laser technology have offered better tools for dealing with irregular astigmatism with finding new surgical methods to improve corneal regularity for the correction of irregular astigmatism.

Topography-linked excimer laser is a potentially effective technique in the treatment of irregular astigmatism after keratoplasty . In fact, customized ablation was shown to be an effective means of treatment of irregular astigmatism due to different etiologies Such as corneal Injuries , scar , or postoperative.

Some of the theoretical advantages of topography-driven photorefractive keratectomy (PRK) are a better astigmatic correction, the possibility of correcting irregular astigmatism, and a smaller ablation volume compared with standard treatments, resulting in better visual performance.

Aim of the work To evaluate the efficacy, safety, and predictability of topography-guided photorefractive keratectomy (PRK) to improve refractive status of patient with irregular Cornea.

Detailed Description

Not available

Basic Information
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Recruitment & Eligibility
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Study & Design
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Trial Locations

Study Timeline

• Study Start: 2017-03-01
• Study First Submitted: 2017-04-26
• Study First Submitted QC: 2017-05-02
• Study First Posted: 2017-05-04
• Primary Completion: 2018-03-01
• Study Completion: 2018-03-01
• Status Verified: 2020-05
• Last Update Submitted: 2020-05-08
• Last Update Posted: 2020-05-11

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 20

Inclusion Criteria

• Patients with irregular corneal astigmatism caused by:

  • Trauma.
  • Non - Central Corneal Scars.
  • Previous corneal surgery.

• With No other abnormalities in the eye.

• Patient is willing to enter the study and sign a consent.

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Exclusion Criteria

• Patients with central corneal scars.
• Patients with central haze interfering with visual acuity.
• Patients with ectasia at corneal graft margins.
• Patients with irregular astigmatism caused by corneal ectasia or keratoconus.
• Patients had refractive surgery with ablations leaving a residual corneal thickness less than 250 μm.

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Study & Design

• Study Type: INTERVENTIONAL
• Study Design: SINGLE_GROUP

Arm && Interventions

Group	Intervention	Description
Corneal Topography	photorefractive keratectomy (PRK)	we will do Corneal Topography for every patient before doing photorefractive keratectomy (PRK) and also after it , to measure the change in the quality of vision and measure the change in the quality of vision

Primary Outcome Measures

Name	Time	Method
Visual Acuity	follow up after 1 day, 1 week, 1 month and 3 months	The measure of the Visual Acuity and Best Corrected Visual acuity Using the Snellen Chart which give use an idea about visual acuity in Metric scale (e.g. 6\\6 , 6\\12)

Secondary Outcome Measures

Name	Time	Method
Refractive State	follow up after 1 day, 1 week, 1 month and 3 months	We will measure the Refractive state of the eye by using the Auto refractor which give us an idea about the refractive state in a Diopteric scale ( e.g. -2D , +4 D) .

Trial Locations

Locations (1)

Assiut University; 🇪🇬 Assiut, Egypt