Abstract
Objectives:to compare the efficacy, safety and predictability of corneal wavefront guided (WFG) and aberration free ablation in single-step transepithelial photorefractive keratectomy (TransPRK) in myopic patients with high pre-existing corneal higher order aberrations (HOAs).
Background: Corneal WFG and aberration free treatments have been proposed as methods to achieve better visual, refractive, and optical outcomes.
Methods:Non-randomized controlled trialwas conducted in El-HekmaEye-LASIK center, Menoufia governorate, Egypt during the period from January 2017 to December 2017. TransPRK was performed to eligible myopic patients with or without astigmatism with corneal HOAs ≥ 0.35 µmat 6 mm diameter utilizing either optimized (aberration free) or corneal WFG patterns (SCHWIND eye-tech-solutions, Kleinostheim, Germany). Uncorrected distance visual acuity (UDVA), manifest and cycloplegic refractions, best spectacle corrected distance visual acuity (CDVA), thorough slit lamp examination and corneal topography were assessed and repeated six months postoperatively.
Results: Six months postoperatively, 97.6% and 100% of patients achieved MRSE within ± 1D with 76.2% and 66.67% of patients achieved UDVA of ≥20/20 in aberration free and corneal WFG groups respectively. Both groups showed increase in spherical and total corneal HOAs, with no significant difference in corneal WFG (p=0.08, p=0.28 respectively) while significantly higher postoperatively in aberration free group (p<0.001, p=0.001 respectively). Coma and trefoil aberrations declined after corneal WFG technique, yet increased after aberration free one.
Conclusions: both aberration free and corneal WFG TransPRK were safe, effective and predictable in treatment of myopia in patients with high pre-existing corneal HOAs at 6 mm diameter with better aberrometric outcomes in corneal WFG group.
Higher-order aberrations after wavefront-optimized photorefractive keratectomy and laser in situ keratomileusis
