title: Intraocular pressure measurement after hyperopic LASIK.
abstract: OBJECTIVE
  Previous studies have shown that Goldmann applanation tonometry (GAT) underestimates intraocular pressure (IOP) following photorefractive keratometry (PRK) and myopic laser in situ keratomileusis (LASIK). The purpose of this study was to evaluate the reliability of intraocular pressure (IOP) measurements by Goldmann applanation tonometry and pneumotonometry (PT) after hyperopic LASIK.
  
  
  METHODS
  The IOPs of 20 eyes of 15 patients who underwent hyperopia LASIK were prospectively evaluated. Central and peripheral IOP were measured with GAT and PT, and central and peripheral corneal thicknesses were measured with ultrasonographic pachymetry. Patients were evaluated preoperatively and at 12 months postoperatively.
  
  
  RESULTS
  Postoperative GAT measurements of IOP made from the central (13.1+/-2.7 mm Hg) and peripheral (13.9+/-3.3 mm Hg) corneal areas were significantly lower (P <0.001) than central IOP measured preoperatively (17.0+/-2.5 mm Hg). Postoperative PT measurements from the central (17.4+/-3.2 mm Hg) and peripheral (17.6+/-2.9 mm Hg) corneal areas were slightly lower than preoperative central IOP (18.4+/-2.4 mm Hg), but not statistically significant. There were no significant differences between central and peripheral IOP measurements using either method.
  
  
  CONCLUSIONS
  The data demonstrate that GAT may underestimate IOP measurement, following hyperopic LASIK.
authors.affiliation: Department of Ophthalmology, The University of Texas Southwestern Medical Center at Dallas, 75390-9057, USA.
authors.forename: Xiaohong
authors.initials: X
authors.lastname: Wang
authors.forename: Joanne
authors.initials: J
authors.lastname: Shen
authors.forename: James P
authors.initials: JP
authors.lastname: McCulley
authors.forename: R Wayne
authors.initials: RW
authors.lastname: Bowman
authors.forename: W Matthew
authors.initials: WM
authors.lastname: Petroll
authors.forename: H Dwight
authors.initials: HD
authors.lastname: Cavanagh
mesh_terms: D000328:Adult; D000368:Aged; D003315:Cornea / Q000601:surgery*; D005260:Female; D006801:Humans; D006956:Hyperopia / Q000601:surgery*; D007429:Intraocular Pressure / Q000502:physiology*; D020731:Keratomileusis, Laser In Situ; D008297:Male; D008875:Middle Aged; D011184:Postoperative Period; D011446:Prospective Studies; D014065:Tonometry, Ocular / Q000379:methods; D016896:Treatment Outcome