title: Method for optimizing topography-guided ablation of highly aberrated eyes with the ALLEGRETTO WAVE excimer laser.
abstract: To evaluate the clinical outcomes of custom topographic neutralizing technique in treating highly aberrated eyes using the WaveLight ALLEGRETTO WAVE Excimer Laser.
  
  
  
  A retrospective consecutive case series of 67 eyes with decentered ablations and 48 eyes with symptomatic small optical zones after previous LASIK underwent topography-guided retreatment with the ALLEGRETTO WAVE. Sixteen keratoconus eyes underwent topographic neutralizing technique photorefractive keratectomy (PRK). The study assessed preoperative and 6-month and 1-year postoperative results regarding best spectacle-corrected visual acuity (BSCVA), uncorrected visual acuity (UCVA), topography, and predictability.
  
  
  
  Sixty-seven eyes with previously decentered optical zones had an improvement of centration from 0.92 mm preoperatively to 0.30 mm postoperatively relative to pupil center (P<.01). Twenty-nine percent of these eyes gained 1 or more lines of BSCVA, whereas 71% had no change in BSCVA. Forty-eight eyes with previously small optical zones had an increase of the central monodioptric optical zone from 3.9 mm to 5.6 mm (P<.01). Nineteen percent of eyes had an improvement of at least 1 line, whereas 75% had no change in BSCVA and 6% lost 1 line. Sixteen keratoconus eyes had custom topographic neutralizing technique PRK as an alternative to penetrating keratoplasty. All eyes had improvement of astigmatism up to 5.00 diopters (D), with a mean change of 1.68+/-1.62 D. Best spectacle-corrected visual acuity was unchanged in 8 (50%) eyes, with 4 (25%) eyes gaining 1 line, 2 (12%) eyes gaining 2 lines, and 2 (12%) eyes losing 1 line of BSCVA at 6 months.
  
  
  
  Management of some highly aberrated eyes is now possible with topography-guided ablation using the WaveLight ALLEGRETTO platform and custom topographic neutralizing technique. Safety was acceptable for small optical zone and decentered ablation retreatments. The topography-guided ablation could be an alternative treatment for keratoconus patients if keratoplasty is otherwise indicated. The algorithms for custom topographic neutralizing technique need further refinement.
authors.affiliation: University of British Columbia and Pacific Laser Eye Centre, Vancouver, British Columbia, Canada. tclin@shaw.ca
authors.forename: David T C
authors.initials: DT
authors.lastname: Lin
authors.forename: Simon R
authors.initials: SR
authors.lastname: Holland
authors.forename: Karolinne Maia
authors.initials: KM
authors.lastname: Rocha
authors.forename: Ronald R
authors.initials: RR
authors.lastname: Krueger
mesh_terms: D000328:Adult; D019781:Corneal Topography / Q000379:methods*; D005260:Female; D006801:Humans; D007640:Keratoconus / Q000601:surgery*; D020731:Keratomileusis, Laser In Situ / Q000379:methods*; D054018:Lasers, Excimer; D008297:Male; D008875:Middle Aged; D018903:Photorefractive Keratectomy / Q000379:methods*; D012030:Refractive Errors / Q000150:complications; D012086:Reoperation; D012189:Retrospective Studies; D016896:Treatment Outcome; D014792:Visual Acuity / Q000502:physiology