title: Photorefractive keratectomy for primary myopia using NIDEK topography-guided customized aspheric transition zone.
abstract: To report the outcomes of topography-guided photorefractive keratectomy (PRK) for the treatment of myopia with or without astigmatism using the customized aspheric transition zone (CATz) ablation algorithm.
  
  
  
  In this study, 335 eyes underwent PRK using the NIDEK Advanced Vision Excimer laser platform (NAVEX). Mean preoperative manifest refraction spherical equivalent was -4.42+/-3.46 diopters (D) (range: -14.50 to -0.50 D). Mean preoperative sphere was -3.94+/-3.43 D (range: -13.00 to -1.00 D), and mean preoperative cylinder was -0.96+/-1.05 D (range: -5.50 to 0.00 D). Refractive outcomes out to 1 year postoperatively were analyzed.
  
  
  
  At least 6 months postoperatively, all eyes maintained or gained lines of best spectacle-corrected visual acuity (BSCVA). There was a 51% increase in the eyes that read 20/16 or better uncorrected compared with preoperative BSCVA. At 1 year postoperative, 252/280 (90%) eyes had BSCVA 20/20 or better. Refractive outcomes within +/-0.50 D were observed in 223/275 (81%) eyes at 3 months, 228/300 (76%) eyes at 6 months, and 187/280 (67%) eyes at 1 year.
  
  
  
  Topography-guided PRK using CATz for the treatment of low, moderate, and high myopia is safe, effective, and predictable.
authors.affiliation: Department of Ophthalmology, Istituto Clinico Humanitas, Rozzano, Milan, Italy. info@vincieye.it
authors.forename: Paolo
authors.initials: P
authors.lastname: Vinciguerra
authors.forename: Fabrizio I
authors.initials: FI
authors.lastname: Camesasca
authors.forename: Harkaran S
authors.initials: HS
authors.lastname: Bains
authors.forename: Silvia
authors.initials: S
authors.lastname: Trazza
authors.forename: Elena
authors.initials: E
authors.lastname: Albè
mesh_terms: D000465:Algorithms; D001251:Astigmatism / Q000503:physiopathology / Q000601:surgery; D003315:Cornea / Q000503:physiopathology / Q000601:surgery*; D019781:Corneal Topography / Q000379:methods*; D005260:Female; D006801:Humans; D054018:Lasers, Excimer / Q000627:therapeutic use*; D008297:Male; D009216:Myopia / Q000503:physiopathology / Q000601:surgery*; D018903:Photorefractive Keratectomy / Q000379:methods*; D016896:Treatment Outcome; D014792:Visual Acuity / Q000502:physiology