Wavefront-guided customized corneal ablation

Abstract

Wavefront guided customized corneal ablations are safe, effective, and predictable. Compared with conventional treatments, wavefront-guided ablations can achieve a reduction in preexisting higher-order aberrations and less induction of new higher-order aberrations, resulting in improved outcomes with contrast sensitivity and visual symptoms under mesopic and scotopic conditions. Wavefront technology is still evolving to address current limitations and to optimize customization of corneal ablations.

Laser in situ keratomileusis in 2010 – a review

“…The femtosecond laser has improved the safety and precision of corneal flap creation in LASIK compared with mechanical microkeratomes. It has the ability to create very uniform and thinner flaps with greater biomechanical stability, less surgically induced refractive error, less HOAs, less epithelial ingrowth, better contrast sensitivity, less dry eye and better visual outcomes 15,92,97–99 . Sub‐Bowman's keratomileusis refers to a customized thinner corneal flap, typically 100 ± 10 µm, that preserves much of the corneas’ biomechanical strength 98 .…”

“…Importantly, the femtosecond laser is associated with significantly fewer intra‐ and postoperative complications 91,92,98,99,101–103 . Epithelial defects, incomplete flaps, irregular flaps and buttonhole flaps are exceptionally rare with the femtosecond laser 92 …”

Minor Influence of Myopic Laser In Situ Keratomileusis on the Posterior Corneal Surface

“…2,3 The most recent ablation algorithms (wavefront-guided or wavefront-optimized) have been shown to induce fewer high-order aberrations than standard algorithms or even to reduce some high-order aberrations, though discrepancies from the expected optical outcomes are still observed. 4,5 Refractive outcomes are also subject to some variability because of regression, 6 hydration, 7 and other factors that lead to empiric adjustments of the ablation nomogram. 8,9 Although the surgical procedure does not directly affect the posterior surface of the cornea and a large proportion of the optical changes can be explained at the level of the anterior corneal surface, 10 a modification in the posterior corneal surface may be expected because the surgery weakens the cornea.…”

Aspheric Ablation Depth as the Target Depth for Enhanced Wavefront-Guided Myopic Retreatments After Laser-Assisted In Situ Keratomileusis

“…21 However, although the increase in total HOA may be reduced by wavefront-guided retreatments, variable results were shown regarding detailed analysis of individual types of HOA. SA, for instance, were reported by some studies to be significantly reduced, 9,13,22,23 whereas others noted no change or even an increase in SA after retreatment.…”