title: Corneal biomechanical properties in 3 corneal transplantation techniques with a dynamic Scheimpflug analyzer.
abstract: OBJECTIVE
  To compare the corneal biomechanical properties of eyes that have undergone penetrating keratoplasty (PK), deep anterior lamellar keratoplasty (DALK), and Descemet stripping automated endothelial keratoplasty (DSAEK).
  
  
  METHODS
  This case-control study comprised 20 post-PK eyes, 14 post-DALK eyes, 15 post-DSAEK eyes, and 50 normal control eyes. A dynamic Scheimpflug analyzer (the Corvis ST) was used to evaluate the corneal biomechanical properties including deformation amplitude (DA) and radius at the highest concavity (R hc).
  
  
  RESULTS
  In post-PK eyes, the mean DA was 1.20 ± 0.13 mm, which was significantly higher than those of the control eyes (1.07 ± 0.09) and the post-DSAEK eyes (1.08 ± 0.12). The DA (1.18 ± 0.18) in the post-DALK eyes was significantly higher than in the control eyes. The R hc in the post-PK (6.34 ± 0.37 mm), -DALK (6.04 ± 1.22), and -DSAEK (6.44 ± 0.58) eyes was significantly smaller than in the control eyes (7.57 ± 0.78).
  
  
  CONCLUSIONS
  The dynamic Scheimpflug analyzer provides a method to obtain new biomechanical information on the cornea such as the DA and R hc, and these parameters differed among eyes that had undergone 3 different types of corneal surgery. Abnormalities in these parameters after the different corneal transplantation techniques may indicate larger deviations in the stress-strain reaction of the cornea and more uncertainty in the intraocular pressure measurements than in normal eyes.
authors.affiliation: Department of Ophthalmology, Osaka University Graduate School of Medicine, Room E7, 2-2 Yamadaoka, Suita, Osaka, 565-0871, Japan, nmaeda@ophthal.med.osaka-u.ac.jp.
authors.forename: Naoyuki
authors.initials: N
authors.lastname: Maeda
authors.forename: Ryotaro
authors.initials: R
authors.lastname: Ueki
authors.forename: Mutsumi
authors.initials: M
authors.lastname: Fuchihata
authors.forename: Hisataka
authors.initials: H
authors.lastname: Fujimoto
authors.forename: Shizuka
authors.initials: S
authors.lastname: Koh
authors.forename: Kohji
authors.initials: K
authors.lastname: Nishida
mesh_terms: D000328:Adult; D000368:Aged; D001696:Biomechanical Phenomena; D016022:Case-Control Studies; D003315:Cornea / Q000503:physiopathology*; D003316:Corneal Diseases / Q000503:physiopathology / Q000601:surgery*; D016039:Corneal Transplantation; D057111:Descemet Stripping Endothelial Keratoplasty; D003941:Diagnostic Techniques, Ophthalmological / Q000295:instrumentation; D004548:Elasticity / Q000502:physiology*; D054459:Elasticity Imaging Techniques; D005260:Female; D006801:Humans; D015948:Keratoplasty, Penetrating; D008297:Male; D008875:Middle Aged