title: Comparative analysis of the efficacy of astigmatic correction after wavefront-guided and wavefront-optimized LASIK in low and moderate myopic eyes.
abstract: OBJECTIVE
  To evaluate and compare the efficacy of the astigmatic correction achieved with laserin situkeratomileusis (LASIK) in eyes with myopic astigmatism using wavefront-guided (WFG) and wavefront-optimized (WFO) ablation profiles.
  
  
  METHODS
  Prospective study included 221 eyes undergoing LASIK: 99 and 122 eyes with low and moderate myopic astigmatism (low and moderate myopia groups). Two subgroups were differentiated in each group according to the ablation profile: WFG subgroup, 109 eyes (45/64, low/moderate myopia groups) treated using the Advanced CustomVue platform (Abbott Medical Optics Inc.), and WFO subgroup, 112 eyes (54/58, low/moderate myopia groups) treated using the EX-500 platform (Alcon). Clinical outcomes were evaluated during a 6-month follow-up, including a vector analysis of astigmatic changes.
  
  
  RESULTS
  Significantly better postoperative uncorrected visual acuity and efficacy index was found in the WFG subgroups of each group (P≤0.041). Postoperative spherical equivalent and cylinder were significantly higher in WFO subgroups (P≤0.003). In moderate myopia group, a higher percentage of eyes with a postoperative cylinder ≤0.25 D was found in the WFG subgroup (90.6%vs65.5%,P=0.002). In low and moderate myopia groups, the difference vector was significantly higher in the WFO subgroup compared to WFG (P<0.001). In moderate myopia group, the magnitude (P=0.008) and angle of error (P<0.001) were also significantly higher in the WFO subgroup. Significantly less induction of high order aberrations were found with WFG treatments in both low and moderate myopia groups (P≤0.006).
  
  
  CONCLUSIONS
  A more efficacious correction of myopic astigmatism providing a better visual outcome is achieved with WFG LASIK compared to WFO LASIK.
authors.affiliation: Ophthalmology Department, Tanta University, Tanta 31527, Egypt; Horus Vision Correction Center, Alexandria 21311, Egypt; Alex LASIK Center, Alexandria 21311, Egypt.
authors.forename: Mounir A
authors.initials: MA
authors.lastname: Khalifa
authors.affiliation: Alex LASIK Center, Alexandria 21311, Egypt.
authors.forename: Mahmoud F
authors.initials: MF
authors.lastname: Alsahn
authors.affiliation: Department of Ophthalmology, University of Alexandria, Alexandria 21543, Egypt.
authors.forename: Mohamed Shafik
authors.initials: MS
authors.lastname: Shaheen
authors.affiliation: Department of Optics, Pharmacology and Anatomy, University of Alicante, Alicante 03690, Spain.
authors.forename: David P
authors.initials: DP
authors.lastname: Pinero
keywords: astigmatism; myopia; wavefront-guided LASIK; wavefront-optimized LASIK