title: [Corneal biomechanics: Corvis® ST parameters after LASIK].
abstract: BACKGROUND
  Corneal refractive surgery alters the biomechanical properties of the cornea.
  
  
  OBJECTIVE
  This study was initiated to evaluate corneal biomechanical parameters after LASIK using a Corvis® ST tonometer (CST).
  
  
  METHODS
  This retrospective study included 51 eyes of 32 myopic patients. All CST measurements were performed 1 day before surgery and at the 1-month follow-up examination. The LASIK procedure included mechanical flap preparation using a Moria SBK microkeratome and an Allegretto excimer laser platform.
  
  
  RESULTS
  Statistically significant differences were observed for mean second applanation length, mean first and second deflection lengths, mean first and second deflection amplitudes, peak distance and radius of curvature. Statistically significant positive correlations were found between the change (Δ) in radius of curvature and Δ in manifest refraction spherical equivalent (MRSE), between the ablation depth and the Δ in intraocular pressure. Applying multiple regression models also revealed statistically significant differences in parameters obtained by CST measurements.
  
  
  CONCLUSIONS
  Several CST parameters were statistically significantly altered by LASIK thereby indicating that flap creation, ablation or both, significantly change the ability of the cornea to absorb or dissipate energy.
authors: Univ.-Augenklinik, Univ.-Klinik Hamburg-Eppendorf, Martinistr. 52, 20246 , Hamburg, Deutschland. a.frings@uke.de.
authors: A
authors: A
authors: Frings
authors: Univ.-Augenklinik, Univ.-Klinik Hamburg-Eppendorf, Martinistr. 52, 20246 , Hamburg, Deutschland.
authors: S J
authors: SJ
authors: Linke
authors: Univ.-Augenklinik, Univ.-Klinik Hamburg-Eppendorf, Martinistr. 52, 20246 , Hamburg, Deutschland.
authors: E L
authors: EL
authors: Bauer
authors: Univ.-Augenklinik, Univ.-Klinik Hamburg-Eppendorf, Martinistr. 52, 20246 , Hamburg, Deutschland.
authors: V
authors: V
authors: Druchkiv
authors: Univ.-Augenklinik, Univ.-Klinik Hamburg-Eppendorf, Martinistr. 52, 20246 , Hamburg, Deutschland.
authors: T
authors: T
authors: Katz
authors: Univ.-Augenklinik, Univ.-Klinik Hamburg-Eppendorf, Martinistr. 52, 20246 , Hamburg, Deutschland.
authors: J
authors: J
authors: Steinberg
mesh_terms: D000328:Adult; D003315:Cornea / Q000503:physiopathology* / Q000601:surgery*; D019781:Corneal Topography / Q000295:instrumentation; D055119:Elastic Modulus; D005260:Female; D006801:Humans; D007429:Intraocular Pressure; D020731:Keratomileusis, Laser In Situ / Q000379:methods*; D008297:Male; D009216:Myopia / Q000503:physiopathology* / Q000601:surgery; D012189:Retrospective Studies; D013314:Stress, Mechanical; D014065:Tonometry, Ocular / Q000295:instrumentation*; D016896:Treatment Outcome
keywords: Ablation; Cornea; Corneal flap; Corneal refractive surgery; Corneal rigidity