title: [Corneal topography analysis after excimer laser photorefractive keratectomy].
abstract: OBJECTIVE
  To study the pattern of ablation, evaluate centration and stability following excimer laser photorefractive keratectomy (PRK) for myopia.
  
  
  METHODS
  Corneal topography of 312 patients (366 eyes) with a month, 3 months and 6 months of follow-up after PRK was examined.
  
  
  RESULTS
  The mean decentration from the pupillary center to ablating center was 0.266 mm. In both eyes, the mean decentration was located supernasally. At one month postoperative examination, uniform ablation was 49.5%, semicircular, keyhole, kidney and dumbbell shaped ablations were 42.9% and central island one was 6.0%. Central island pattern affected the best corrected visual acuity greatly. High myopia began regression at 1-3 months after PRK.
  
  
  CONCLUSIONS
  Corneal topography is essential for evaluating surface changes after PRK. Long-time stability issues are answered with continued topographic follow-up.
authors.affiliation: Department of Ophthalmology, Rui Jin Hospital, Shanghai Second Medical University, Shanghai 200025.
authors.forename: Y
authors.initials: Y
authors.lastname: Qi
authors.forename: J
authors.initials: J
authors.lastname: Lian
authors.forename: W
authors.initials: W
authors.lastname: Deng
authors.forename: D
authors.initials: D
authors.lastname: Zhou
authors.forename: K
authors.initials: K
authors.lastname: Wang
mesh_terms: D019781:Corneal Topography; D006801:Humans; D054018:Lasers, Excimer; D009216:Myopia / Q000503:physiopathology / Q000601:surgery*; D018903:Photorefractive Keratectomy / Q000009:adverse effects / Q000379:methods; D014792:Visual Acuity