Induced Ocular Higher-Order Aberrations After Photorefractive Keratectomy versus Laser-Assisted In Situ Keratomileusis for Myopia: A Systematic Review and Meta-Analysis.
TL;DR
The overall PRK advantage in total ocular HOAs is small and dependent on ablation profile and platform rather than procedure type alone, and wavefront-guided PRK may offer a modest optical advantage over LASIK, while wavefront-optimized outcomes are less certain.
Abstract
TOPIC Do PRK and LASIK differ in induced ocular higher-order aberrations (HOAs) in myopic adults, and does this vary by ablation profile or excimer laser platform? CLINICAL RELEVANCE PRK and LASIK are among the most widely performed refractive procedures worldwide, and both remain standard-of-care options for myopic correction. Despite comparable refractive outcomes, patients frequently report glare, halos, and reduced contrast sensitivity, symptoms linked to induced ocular HOAs. Whether PRK or LASIK confers an optical advantage at the whole-eye level remains unresolved, with prior syntheses focusing primarily on visual acuity and refractive outcomes rather than whole-eye wavefront metrics.
Methods
MEDLINE, Embase, CENTRAL, and Web of Science were searched from inception to September 2, 2025 (PROSPERO: CRD420251018863). Comparative studies of PRK versus LASIK in myopic adults reporting induced ocular HOAs were eligible, including randomized trials, prospective cohorts, contralateral-eye studies, and matched retrospective designs. Risk of bias was assessed using RoB 2 and ROBINS-I, and random-effects meta-analyses were performed with prespecified subgroup analyses by ablation profile and meta-regression.
Results
Thirteen studies contributed to the primary analysis. PRK induced fewer total ocular HOAs than LASIK overall (MD -0.05 μm; 95% CI: -0.08 to -0.02; I2 = 71%). Wavefront-guided treatments consistently favoured PRK (10 comparisons; 411 PRK vs 393 LASIK eyes; MD -0.07 μm; 95% CI: -0.11 to -0.03), while wavefront-optimized treatments showed a non-significant trend favouring LASIK (3 comparisons; MD +0.02 μm; 95% CI: -0.04 to +0.08). Platform analyses favoured PRK on Technolas 217z and showed no clear difference on VISX Star systems. Ocular spherical aberration and coma did not differ significantly, though leave-one-out sensitivity analyses favoured PRK for both.
Conclusion
Evidence quality was low, limited by high heterogeneity and predominantly observational designs. The overall PRK advantage in total ocular HOAs is small and dependent on ablation profile and platform rather than procedure type alone. Wavefront-guided PRK may offer a modest optical advantage over LASIK, while wavefront-optimized outcomes are less certain. PRK and LASIK should not be considered optically equivalent, and procedure selection should incorporate ablation strategy and excimer platform rather than procedural preference alone.