title: The impact of central corneal thickness on intraocular pressure measured by non-contact tonometry.
abstract: OBJECTIVE
  To investigate the impact of central corneal thickness (CCT) on the intraocular pressure (IOP) measurement by non-contact tonometry (NCT).
  
  
  METHODS
  Eye examination data of normal volunteers aged between 18-96 years and intraocular pressure less than 22 mmHg were retrospectively reviewed. Subjects with possible conditions that affected the results of CCT and IOP measurement by NCT were excluded. The data of CCT and IOP measurements by NCT were obtained. Linear and multiple regression analysis were used to evaluate the influence of CCT and age on IOP measurement by NCT.
  
  
  RESULTS
  Four hundred and thirty seven eyes of 437 subjects were enrolled. The mean age was 49.05 +/- 18.84 years. The average CCT was 524.56 +/- 32.40 microns and the mean IOP measurement by NCT was 13.85 +/- 2.81 mmHg. Linear regression model showed a significant negative correlation between CCT and subject age (p < 0.001), but had a positive correlation between CCT and IOP measurement by NCT (p = 0.006).
  
  
  CONCLUSIONS
  CCT has a significant impact on IOP measurement by NCT. The finding suggests that CCT is an important parameter for interpretation of IOP measurement by NCT.
authors.affiliation: Department of Ophthalmology, Faculty of Medicine, Prince of Songkla University Songkhla, Thailand. wboonchai@gmail.com
authors.forename: Boonchai
authors.initials: B
authors.lastname: Wangsupadilok
authors.forename: Orasa
authors.initials: O
authors.lastname: Horatanaruang
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D003315:Cornea / Q000033:anatomy & histology* / Q000502:physiology*; D005260:Female; D006801:Humans; D007429:Intraocular Pressure / Q000502:physiology*; D008297:Male; D008875:Middle Aged; D012044:Regression Analysis; D012189:Retrospective Studies; D013785:Thailand; D014065:Tonometry, Ocular / Q000295:instrumentation / Q000379:methods*; D055815:Young Adult