NCT05829980

Contoura vs Wavefront Optimized Ablation

Contoura Topography-guided Ablation Versus Wavefront-optimized Ablation for Correction of Astigmatism

• Status: Unknown
• Phase: —
• Study type: Observational
• Enrollment: 128 (estimated)
• Sponsor: Hebatallah MT Abdelmoniem · Academic / Other
• Sex: All
• Age: 18 Years – 45 Years
• Healthy volunteers: —

Summary

To evaluate the efficacy, safety and accuracy of Contoura topography-guided LASIK \& PRK in comparison to Wavefront optimized LASIK \& PRK in virgin eyes with astigmatism.

Detailed description

In Upper Egypt, The second principal cause of blindness was uncorrected refractive errors accounting for 16% of sample population. It was reported that astigmatism (defined as cylinder power \> 0.5 D) was the most common refractive errors in children and adults followed by hyperopia and myopia. Laser vision correction has been established over the last 2 decades as a safe and effective intervention to treat refractive errors, being one of the main techniques practiced globally. However, many subjects after LASIK had uncorrected distance visual acuity (UDVA) greater than 1.0, they complain about poor night vision, glare, and double vision. As studies have shown that every 1° deviation of the astigmatic axis could result in loss of correction of 3.3%. Even residual astigmatism less than 0.50D could have an actual impact on visual quality. Excimer laser ablation used in the correction of refracted errors especially astigmatism may reduce quality of vision, and that is attributed to the induced optical aberrations. The most prevalent of these optical aberrations is the spherical aberration. Among multiple sophisticated profiles that developed to optimize visual outcomes, wavefront optimized profile which compensate for corneal curvature to reduce spherical aberration. The topographic guided profiles which consider the shape of the anterior corneal surface. Contoura topography guided ablation corrects astigmatic power and axis to create a more uniform, aberration-free cornea. Treating astigmatism can be challenging as the conventional patterns of Excimer laser treatment of astigmatism is known to be less predictable than that of spherical refractive errors.

Conditions

• Astigmatism

Interventions

Type	Name	Description
PROCEDURE	Laser assisted in-situ keratomileusis	Laser-Assisted In Situ Keratomileusis is a procedure that permanently changes the shape of the cornea using an excimer laser and the mechanical microkeratome (a blade device) used to cut a flap in the cornea.
PROCEDURE	Photorefractive keratectomy	Photorefractive keratectomy is a laser refractive procedure used to ablate the corneal stroma to correct refractive errors without cutting flap

Timeline

• Start date: 2023-06-01
• Primary completion: 2024-12-01
• Completion: 2025-04-01
• First posted: 2023-04-26
• Last updated: 2023-04-26