title: Pentacam Scheimpflug evaluation of corneal volume after LASIK.
abstract: OBJECTIVE
  To assess the change in corneal volume and laser ablation volume over time after LASIK using a rotating Scheimpflug camera.
  
  
  METHODS
  Twenty-six patients (49 eyes) underwent LASIK. Pentacam Scheimpflug measurements were performed pre- and postoperatively at 1, 3, 7, 15, and 30 days. Central corneal thickness, total corneal volume (10-mm diameter), and partial corneal volumes (3, 5, and 7 mm) based on the apex of the cornea, were measured. Main outcome measures were differences between pre- and postoperative volume measurements of total and partial corneal regions, volume changes over time postoperatively, and comparison between laser ablation volume and corneal volume.
  
  
  RESULTS
  A strong linear relationship was noted between spherical equivalent refraction and laser ablation volume (r = -0.931, P < .0001). Furthermore, 30 days after LASIK, a strong linear relationship was noted between planned thickness and achieved thickness (r = 0.9457, P < .001). Corneal volumes for 3-, 5-, and 7-mm diameter regions significantly decreased over time postoperatively (one-way analysis of variance, P < .05).
  
  
  CONCLUSIONS
  Alterations in corneal volume correlated with laser ablation volume when the diameter of the region considered was 3, 5, or 7 mm from the corneal apex.
authors.affiliation: From Vision Institute, Federal University of São Paulo, Department of Ophthalmology, São Paulo, Brazil. camilamg@oftalmo.epm.br
authors.forename: Camila M Gadelha R
authors.initials: CM
authors.lastname: Diniz
authors.forename: Rossen M
authors.initials: RM
authors.lastname: Hazarbassanov
authors.forename: Ester
authors.initials: E
authors.lastname: Yamazaki
authors.forename: Celina
authors.initials: C
authors.lastname: Murata
authors.forename: Felipe
authors.initials: F
authors.lastname: Mallmann
authors.forename: Mauro
authors.initials: M
authors.lastname: Campos
mesh_terms: D000328:Adult; D000886:Anthropometry; D001251:Astigmatism / Q000601:surgery*; D003315:Cornea / Q000473:pathology*; D003941:Diagnostic Techniques, Ophthalmological; D006801:Humans; D020731:Keratomileusis, Laser In Situ / Q000379:methods*; D054018:Lasers, Excimer / Q000627:therapeutic use*; D008875:Middle Aged; D009216:Myopia / Q000601:surgery*; D010781:Photography / Q000379:methods; D011446:Prospective Studies