title: Factors Predicting Refractive Outcomes After Deep Anterior Lamellar Keratoplasty in Keratoconus.
abstract: OBJECTIVE
  To determine the factors that predict refraction, mean keratometry, and keratometric astigmatism after deep anterior lamellar keratoplasty (DALK) in keratoconus.
  
  
  METHODS
  Consecutive interventional case series.
  
  
  METHODS
  This study enrolled 194 consecutive eyes of 181 patients with keratoconus who underwent DALK using the big-bubble technique. Indications for surgery included contact lens intolerance or poor corrected visual acuity. Univariate analyses and analysis of covariance were used to investigate recipient-, surgical-, and postoperative-related variables capable of predicting refractive outcomes, including mean keratometry, keratometric astigmatism, and spherical equivalent refraction.
  
  
  RESULTS
  The mean patient age was 27.9 ± 8.2 years, and the patients were followed for 35.9 ± 18.2 months postoperatively. Preoperative mean keratometry (P = .007), time interval from surgery to running suture removal (P = .01), and suture-tract vascularization (P = .04) significantly influenced postoperative mean keratometry. Vitreous length predicted postoperative spherical equivalent (P = .03). Postoperative keratometric astigmatism failed to demonstrate any significant correlation with the preoperative, surgical, and postoperative variables. Postoperative refractive outcomes did not change relative to patient age and sex, central and peripheral corneal thickness, recipient trephination size, surgical technique (big-bubble vs manual dissection DALK), duration of steroid administration, and elevated intraocular pressure.
  
  
  CONCLUSIONS
  Keratoconus patients with an elongated posterior segment and/or steep corneas should be informed of the need for postoperative optical correction after DALK. Running suture removal should be postponed for as long as possible if there is no suture-related complication.
authors.affiliation: Ophthalmic Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran. Electronic address: sepehrfeizi@yahoo.com.
authors.forename: Sepehr
authors.initials: S
authors.lastname: Feizi
authors.affiliation: Ophthalmic Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
authors.forename: Mohammad Ali
authors.initials: MA
authors.lastname: Javadi
mesh_terms: D000293:Adolescent; D000328:Adult; D001251:Astigmatism / Q000503:physiopathology; D019781:Corneal Topography; D016039:Corneal Transplantation / Q000379:methods*; D005260:Female; D006801:Humans; D007640:Keratoconus / Q000503:physiopathology / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D012029:Refraction, Ocular / Q000502:physiology*; D012307:Risk Factors; D016896:Treatment Outcome; D014792:Visual Acuity / Q000502:physiology*; D055815:Young Adult