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

NCT ID: NCT03140046

Last Updated: 2020-05-11

Basic Information

• Recruitment Status: COMPLETED
• Clinical Phase: NA
• Total Enrollment: 20 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2017-03-01
• Study Completion Date: 2018-03-01

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.

Conditions

Irregular Astigmatism

Study Design

• Allocation Method: NA
• Intervention Model: SINGLE_GROUP
• Primary Study Purpose: TREATMENT
• Blinding Strategy: NONE

Study Groups

Corneal Topography

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

Group Type: EXPERIMENTAL

photorefractive keratectomy (PRK)

Intervention Type: PROCEDURE

The cornea will be ablated while the patient fixating on target light under constant eye-tracking control. The ablations will be made using the "ALLEGRETTO X 500WAVE excimer laser" (WaveLight Laser Technologie AG).

Interventions

photorefractive keratectomy (PRK)

The cornea will be ablated while the patient fixating on target light under constant eye-tracking control. The ablations will be made using the "ALLEGRETTO X 500WAVE excimer laser" (WaveLight Laser Technologie AG).

Intervention Type: PROCEDURE

Other Intervention Names

PRK

Eligibility Criteria

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.

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.

• Eligible Sex: ALL
• Accepts Healthy Volunteers: No

Sponsors

Assiut University

OTHER

Sponsor Role: lead

Responsible Party

Ahmed Abdelsamee Mohammed

Dr

Responsibility Role: PRINCIPAL_INVESTIGATOR

Locations

Assiut University

Asyut, , Egypt

Countries

Egypt

Other Identifiers

PRK

Identifier Type: -

Identifier Source: org_study_id