title: Ocular biomechanical metrics by CorVis ST in healthy Brazilian patients.
abstract: OBJECTIVE
  To evaluate ocular biomechanical metrics given by the CorVis ST (Oculus, Inc., Berlin, Germany) in a population of healthy Brazilian patients.
  
  
  METHODS
  An observational and cross-sectional study involving 1 eye randomly selected from 90 healthy patients. Studied parameters (including deformation amplitude, first applanation time, highest concavity time, second applanation time, first applanation length, second applanation length, curvature radius highest concavity, curvature radius normal, velocity in, and velocity out) derived from the CorVis ST were correlated to central corneal thickness from the Pentacam (Oculus, Inc.). Differences between data on the basis of gender were evaluated.
  
  
  RESULTS
  Mean patient age was 35.80 ± 12.83 years (range: 21.07 to 78.84 years). Mean central corneal thickness was 547.50 ± 32.00 μm (range: 490 to 647 μm) and mean spherical equivalent refraction was -3.29 ± 3.69 diopters (range: -9.50 to +10.37 diopters). Mean deformation amplitude was 1.05 ± 0.08 mm (range: 0.91 to 1.26 mm). Highest concavity time was 18.38 ± 0.93 ms (range: 16.95 to 21.07 ms). Intraocular pressure was 16.43 ± 2.15 mm Hg (range: 11.50 to 21.0 mm Hg). First applanation time was 8.32 ± 0.33 ms (range: 7.53 to 9.12 ms) and second applanation time was 23.80 ± 0.44 ms (range: 22.76 to 24.95 ms). First applanation length (max) was 2.07 ± 0.38 mm (range: 1.20 to 3.10 mm) and second applanation length (max) was 2.37 ± 0.47 mm (range: 1.33 to 4.12 mm). Curvature radius highest concavity was 11.09 ± 2.06 mm (range: 7.58 to 15.98 mm) and curvature radius normal was 7.59 ± 0.67 mm (range: 6.82 to 11.02 mm). Velocity in was 0.21 ± 0.05 m/s (range: 0.16 to 0.72 m/s) and velocity out was -0.33 ± 0.07 m/s (range: -0.72 to -0.20 m/s). Studied parameters were not associated with gender.
  
  
  CONCLUSIONS
  Eight of 11 ocular biomechanical metrics given by the CorVis ST were associated with central corneal thickness, but the influence of central corneal thickness on these measurements was low.
authors.forename: Bruno Freitas
authors.initials: BF
authors.lastname: Valbon
authors.forename: Renato
authors.initials: R
authors.lastname: Ambrósio
authors.forename: Bruno Machado
authors.initials: BM
authors.lastname: Fontes
authors.forename: Allan
authors.initials: A
authors.lastname: Luz
authors.forename: Cynthia J
authors.initials: CJ
authors.lastname: Roberts
authors.forename: Milton Ruiz
authors.initials: MR
authors.lastname: Alves
mesh_terms: D000328:Adult; D000368:Aged; D001696:Biomechanical Phenomena; D001938:Brazil; D003315:Cornea / Q000033:anatomy & histology* / Q000502:physiology*; D003430:Cross-Sectional Studies; D004548:Elasticity / Q000502:physiology*; D005260:Female; D064368:Healthy Volunteers; D006801:Humans; D007429:Intraocular Pressure / Q000502:physiology*; D008297:Male; D008875:Middle Aged; D009929:Organ Size; D014065:Tonometry, Ocular / Q000295:instrumentation*; D055815:Young Adult