title: Two-stage laser in situ keratomileusis to correct refractive errors after penetrating keratoplasty.
abstract: OBJECTIVE
  To evaluate the effect of a two-stage laser in situ keratomileusis (LASIK) procedure on eyes with high astigmatism and/or anisometropia after penetrating keratoplasty.
  
  
  METHODS
  Eleven postoperative penetrating keratoplasty eyes were included in a prospective, non-controlled study. All patients had at least 4.00 D of astigmatism and/or at least 3.00 D of anisometropia and were spectacle and contact lens intolerant. Two-stage LASIK was performed; in the first stage a hinged corneal flap 160 microm in thickness and 9 mm in diameter was created. After stabilization of corneal shape (1 to 3 months after keratotomy), the corneal flap was lifted and laser refractive treatment (second stage) was performed.
  
  
  RESULTS
  After the first stage, a statistically significant reduction in refractive astigmatism (P<.01) was recorded. In all eyes but one, best spectacle-corrected visual acuity was maintained or improved after the procedure. Three months after the second stage, refractive astigmatism in 8 of 11 eyes (73%) was within +/- 1.00 D, and spherical equivalent refraction in 9 of 11 eyes (82%) was within +/- 1.00 D of intended correction. Preoperative irregular astigmatism persisted in three patients (3 eyes) who could not be corrected within +/- 1.00 D of refractive astigmatism and/or +/- 1.00 D of intended spherical equivalent refraction. In one eye, an interface infiltrate developed shortly after creation of the flap, and resulted in limited melting.
  
  
  CONCLUSIONS
  A two-stage LASIK procedure improved visual acuity and refraction in postoperative penetrating keratoplasty eyes with high astigmatism and/or anisometropia. Complications were uncommon but can lead to loss of vision.
authors.affiliation: Villa Serena Hospital, Department of Ophthalmology, Forli, Italy. mbusin@alinet.it
authors.forename: Massimo
authors.initials: M
authors.lastname: Busin
authors.forename: Luca
authors.initials: L
authors.lastname: Zambianchi
authors.forename: Federico
authors.initials: F
authors.lastname: Garzione
authors.forename: Vincenzo
authors.initials: V
authors.lastname: Maucione
authors.forename: Scipione
authors.initials: S
authors.lastname: Rossi
mesh_terms: D000328:Adult; D000368:Aged; D015858:Anisometropia / Q000209:etiology / Q000601:surgery*; D001251:Astigmatism / Q000209:etiology / Q000601:surgery*; D003315:Cornea / Q000601:surgery*; D019781:Corneal Topography; D006801:Humans; D020731:Keratomileusis, Laser In Situ / Q000379:methods*; D015948:Keratoplasty, Penetrating / Q000009:adverse effects*; D008875:Middle Aged; D011183:Postoperative Complications; D011446:Prospective Studies; D012029:Refraction, Ocular; D013524:Surgical Flaps; D013997:Time Factors; D014792:Visual Acuity