title: Examination of ocular biomechanics with a new Scheimpflug technology after corneal refractive surgery.
abstract: OBJECTIVE
  To analyze the early results of a new device measuring ocular biomechanics after corneal refractive surgery.
  
  
  METHODS
  Thirty nine refractive surgery patients were enrolled in the study (age: 32.6±9.9 years). Laser in situ keratomileusis (LASIK) was performed on 52 eyes of 26 patients and photorefractive keratectomy (PRK) was done on 26 eyes of 13 patients. Ten device-specific biomechanical parameters, intraocular pressure (IOP) and pachymetry were measured preoperatively and at day 1, week 1 and month 1 after the surgeries with a new technology based on Scheimpflug imaging (CorVis ST, Oculus).
  
  
  RESULTS
  In case of LASIK, the day after the procedure, radius values showed significant differences compared to preoperative data. One month after surgery, radius values, velocity of the second applanation and pachymetry showed significant differences compared to preoperative data. In case of PRK, the day after the procedure, significant differences in IOP, maximum amplitude at the apex, A1 time, A2 velocity and highest concavity time were measured. After 1 month of PRK, there were no differences in the parameters compared to preoperative data except pachymetry.
  
  
  CONCLUSIONS
  We observed that some specific biomechanical parameters changed measured with CorVis ST after LASIK and PRK, in the early postoperative time. However, most of these parameters remain unchanged after one month of LASIK and PRK compared to preoperative data.
authors.affiliation: Orbi-Dent Health and Laser Center, Debrecen, Hungary.
authors.forename: Ziad
authors.initials: Z
authors.lastname: Hassan
authors.affiliation: Department of Ophthalmology, Medical and Health Science Center, University of Debrecen, Debrecen, Hungary.
authors.forename: Laszlo
authors.initials: L
authors.lastname: Modis
authors.affiliation: Department of Ophthalmology, Medical and Health Science Center, University of Debrecen, Debrecen, Hungary.
authors.forename: Eszter
authors.initials: E
authors.lastname: Szalai
authors.affiliation: Department of Ophthalmology, Medical and Health Science Center, University of Debrecen, Debrecen, Hungary.
authors.forename: Andras
authors.initials: A
authors.lastname: Berta
authors.affiliation: Department of Ophthalmology, Medical and Health Science Center, University of Debrecen, Debrecen, Hungary. Electronic address: nemeth222@yahoo.com.
authors.forename: Gabor
authors.initials: G
authors.lastname: Nemeth
mesh_terms: D000328:Adult; D003315:Cornea / Q000503:physiopathology* / Q000601:surgery; D063171:Corneal Pachymetry / Q000379:methods*; D004548:Elasticity; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007429:Intraocular Pressure / Q000502:physiology*; D008297:Male; D011184:Postoperative Period; D011446:Prospective Studies; D012029:Refraction, Ocular / Q000502:physiology*; D054140:Refractive Surgical Procedures; D014065:Tonometry, Ocular
keywords: CorVis ST; LASIK; Ocular biomechanics; PRK; Scheimpflug technology