title: Topography-guided custom ablation for irregular corneal astigmatism using the NIDEK NAVEX Laser System.
abstract: To determine whether topography-guided custom ablation produces acceptable outcomes in the treatment of irregular corneal astigmatism caused by previous corneal surgery or corneal disease.
  
  
  
  Thirteen eyes of nine patients who had irregular corneal astigmatism from previous corneal surgery or corneal disease were treated with customized aspheric treatment zone (CATz) ablations using the NIDEK Advanced Vision Excimer Laser System (NAVEX). Changes in corneal surface regularity index, surface asymmetry index, asymmetry component, corneal and ocular higher order aberrations, uncorrected visual acuity, and best spectacle-corrected visual acuity (BSCVA) were analyzed using Wilcoxon and paired t tests. A P value < .05 was considered statistically significant.
  
  
  
  After CATz treatment, 62% of eyes (8 of 13) showed an increase in BSCVA. Improvements in both the surface asymmetry index and asymmetry components were statistically significant after CATz treatment (P < .05).
  
  
  
  Topography-guided custom ablation can be safe and effective in the management of irregular corneal astigmatism due to previous corneal surgery or corneal disease.
authors.affiliation: Nagoya Eye Clinic, Nagoya, Aichi, Japan. lasik@aqua.ocn.ne.jp
authors.forename: Yoko
authors.initials: Y
authors.lastname: Yoshida
authors.forename: Tomoaki
authors.initials: T
authors.lastname: Nakamura
authors.forename: Shuya
authors.initials: S
authors.lastname: Hara
authors.forename: Norihiko
authors.initials: N
authors.lastname: Yoshida
authors.forename: Takashi
authors.initials: T
authors.lastname: Kojima
authors.forename: Kazuo
authors.initials: K
authors.lastname: Ichikawa
mesh_terms: D001251:Astigmatism / Q000209:etiology / Q000601:surgery*; D003316:Corneal Diseases / Q000209:etiology / Q000601:surgery*; D019781:Corneal Topography; D006801:Humans; D020731:Keratomileusis, Laser In Situ / Q000009:adverse effects / Q000379:methods*; D054018:Lasers, Excimer; D012086:Reoperation; D016896:Treatment Outcome; D014792:Visual Acuity / Q000502:physiology