title: Photorefractive keratectomy with customized segmental ablation to correct irregular astigmatism after laser in situ keratomileusis.
abstract: OBJECTIVE
  To correct irregular astigmatism after laser in situ keratomileusis (LASIK) with customized segmental ablation using the Nidek OPD-Scan (ARK-10000) to guide the Nidek EC-5000 excimer laser with the Final Fit software.
  
  
  METHODS
  One eye of a patient that had undergone LASIK and one enhancement was treated using photorefractive keratectomy (PRK) with customized segmental ablation. OPD-Scan maps were analyzed before and after surgery. The Final Fit software was used to link the OPD-Scan to the EC-5000 laser to guide the customized ablation.
  
  
  RESULTS
  At 1 month postoperatively, best spectacle-corrected visual acuity had improved from 20/20-2 to 20/15-2, the patient's subjective evaluation of vision was markedly improved, and the postoperative OPD-Scan maps appeared more regular.
  
  
  CONCLUSIONS
  Customized segmental ablation can be performed using the Nidek OPD-Scan and Final Fit software to improve best spectacle-corrected visual acuity and minimize irregular astigmatism, which may result from prior surgical procedures.
authors.affiliation: Gimbel Eye Centre, Calgary, Alberta, Canada. hvgimbel@gimbel.com
authors.forename: H V
authors.initials: HV
authors.lastname: Gimbel
authors.forename: S B
authors.initials: SB
authors.lastname: Stoll
mesh_terms: D001251:Astigmatism / Q000209:etiology / Q000601:surgery*; D003315:Cornea / Q000601:surgery*; D019781:Corneal Topography; D006801:Humans; D020731:Keratomileusis, Laser In Situ / Q000009:adverse effects*; D054018:Lasers, Excimer; D008297:Male; D008875:Middle Aged; D018903:Photorefractive Keratectomy / Q000379:methods*; D016896:Treatment Outcome; D014792:Visual Acuity