title: Comparability of Icare Pro Rebound Tonometer with Goldmann Applanation and Noncontact Tonometer in a Wide Range of Intraocular Pressure and Central Corneal Thickness.
abstract: OBJECTIVE
  To evaluate the agreement between the reading values of the Goldmann applanation tonometer (GAT), Icare Pro rebound tonometer (IRT) and noncontact tonometer (NCT) in glaucoma patients.
  
  
  METHODS
  This cross-sectional study comprised 292 eyes of 292 patients selected from a glaucoma outpatient clinic. The intraocular pressure (IOP) was measured sequentially, at a 10-min interval each, in the following order: NCT, IRT and GAT. The central corneal thickness (CCT) was measured using Pentacam HR before the IOP measurements.
  
  
  RESULTS
  The mean IOPs measured by the GAT, NCT and IRT were 20.17 ± 6.73 mm Hg (range: 4-48), 19.77 ± 6.88 mm Hg (range: 3-46) and 19.30 ± 5.15 mm Hg (range: 7.30-44.5), respectively. The correlation coefficients of the GAT and IRT, NCT and IRT, and GAT and NCT measurements were r(2) = 0.673, r(2) = 0.663 and r(2) = 0.938 (all p < 0.001), respectively. The IRT tends to overestimate in the low GAT-measured IOPs, whereas it underestimates in high GAT-measured IOPs. The measurements of all 3 devices were also correlated with the CCT at a statistically significant level (GAT: r(2) = 0.063, NCT: r(2) = 0.063, IRT: r(2) = 0.058).
  
  
  CONCLUSIONS
  The agreement between the IRT and GAT measurements is higher in the IOP range of 9-22 mm Hg, whereas significant discrepancies occur as the IOP deviates from normal values. The variability of the IRT and GAT measurements over a wide range of CCT is minimal.
authors.affiliation: Cerrahpasa Medical School, Istanbul University, Istanbul, Turkey.
authors.forename: Nevbahar
authors.initials: N
authors.lastname: Tamçelik
authors.forename: Eray
authors.initials: E
authors.lastname: Atalay
authors.forename: Erdogan
authors.initials: E
authors.lastname: Cicik
authors.forename: Ahmet
authors.initials: A
authors.lastname: Özkök
mesh_terms: D000368:Aged; D003430:Cross-Sectional Studies; D005260:Female; D005901:Glaucoma / Q000175:diagnosis*; D006801:Humans; D007429:Intraocular Pressure / Q000502:physiology; D008297:Male; D008875:Middle Aged; D009798:Ocular Hypertension / Q000175:diagnosis*; D011446:Prospective Studies; D012044:Regression Analysis; D015203:Reproducibility of Results; D014065:Tonometry, Ocular / Q000295:instrumentation*