title: Late onset corneal ectasia after LASIK surgery.
abstract: OBJECTIVE
  To report late onset corneal ectasia following myopic LASIK.
  
  
  METHODS
  A retrospective cohort case series. Nineteen patients with late onset corneal ectasia following LASIK procedure were examined at The Eye Center, Riyadh, Saudi Arabia. Patients underwent LASIK for myopia with spherical equivalent ranging from -1.4 to -13.75 diopters. Age and gender, history of systemic or local diseases, and time of onset of corneal ectasia were recorded. Eye examination and corneal topographical analyses were done before and after LASIK surgery.
  
  
  RESULTS
  Nineteen patients (29 eyes) with late onset corneal ectasia were identified from 1998 to 2008 in 13 male and six female patients. The mean follow-up period was 108 ± 23 months (range 72-144 months). No patient had pre-operative identifiable risk factors for corneal ectasia and the mean time of onset was 57 ± 24 months (range 24-120 months after LASIK). The pre-operative values included mean central pachymetry 553 ± 25 μm, mean keratometry reading of 42.9 ± 1.5 diopters, average oblique cylinder of 1.4 ± 1.2 diopters, posterior surface elevation of 26 ± 2.1 diopters, corneal flap thickness of 160 μm, mean spherical equivalent of -5.6 ± 3.6 diopters, and calculated residual corneal stromal bed thickness was 288 ± 35 μm. Three (5 eyes) patients developed ectasia after pregnancy. Three (4 eyes) patients developed corneal ectasia following severe adenoviral keratoconjunctivitis and had positive PCR for adenovirus type 8.
  
  
  CONCLUSIONS
  Corneal ectasia may develop many years after LASIK surgery and symptoms could go undetected for some time. Pregnancy and adenoviral keratoconjunctivitis occurred post-operatively in six patients.
authors: The Eye Center and the Eye Foundation for Research in Ophthalmology, Riyadh, Saudi Arabia.
authors: Ashraf
authors: A
authors: Said
authors: Issam H
authors: IH
authors: Hamade
authors: Khalid F
authors: KF
authors: Tabbara
keywords: Adenoviral keratoconjunctivitis; Adenovirus; Corneal ectasia; Corneal topography; Keratoconus; LASIK
references: J Refract Surg. 2007 Jun;23(6):620-2
references: 17598583
references: Cornea. 2004 Jul;23(5):447-57
references: 15220728
references: Endocrinology. 2009 Jun;150(6):2692-9
references: 19213838
references: J Cataract Refract Surg. 2007 Sep;33(9):1530-8
references: 17720066
references: Arch Ophthalmol. 2008 Dec;126(12):1655-63
references: 19064844
references: Cornea. 2007 Sep;26(8):983-91
references: 17721301
references: J Cataract Refract Surg. 2007 Apr;33(4):583-90
references: 17397729
references: J Refract Surg. 2004 Sep-Oct;20(5 Suppl):S718-22
references: 15521275
references: J Cataract Refract Surg. 2008 Mar;34(3):510-3
references: 18299080
references: Cornea. 2006 May;25(4):388-403
references: 16670474
references: Ann N Y Acad Sci. 2009 Apr;1160:329-35
references: 19416214
references: J Cataract Refract Surg. 2003 Jun;29(6):1222-5
references: 12842694
references: Ophthalmology. 2008 Jan;115(1):37-50
references: 17624434
references: Am J Ophthalmol. 2002 Nov;134(5):771-3
references: 12429260
references: Ophthalmology. 2008 Dec;115(12):2181-2191.e1
references: 18692245
references: Am J Ophthalmol. 2008 May;145(5):813-8
references: 18328998
references: J Cataract Refract Surg. 2001 Nov;27(11):1796-802
references: 11709254
references: Ann N Y Acad Sci. 2009 Apr;1160:322-8
references: 19416213
references: Ophthalmology. 2006 Sep;113(9):1618-22
references: 16949446
references: J Clin Microbiol. 1996 Sep;34(9):2113-6
references: 8862567