TJ-CEO
2012 , Vol 7 , Num 3
Clinical Comparison of Rebound Tonometer with Goldmann Applanation Tonometer: Effects of Central Corneal Thickness
1M.D. Asistant Professor, Baskent University, Faculty of Medicine, Department of Ophthalmology, Ankara/TURKEY2M.D. Professor, Baskent University, Faculty of Medicine, Department of Ophthalmology, Ankara/TURKEY
3M.D. Associate Professor, Baskent University, Faculty of Medicine, Department of Ophthalmology, Ankara/TURKEY
4M.D. Asistant Professor, Baskent University, Faculty of Medicine, Department of Ophthalmology, İstanbul/TURKEY
5M.D., Baskent University, Faculty of Medicine, Department of Biostatistics, Ankara/TURKEY Purpose: This clinical study was conducted to compare the performance of a rebound tonometer with that of the Goldmann applanation tonometer (GAT) in the measurement of intraocular pressure (IOP) and to evaluate the effect of central corneal thickness (CCT) on IOP measurement with both devices.
Materials and Methods: One hundred and sixty-five healthy subjects were tested using rebound tonometer and GAT by two observers. The patients were divided into 3 groups according to CCT measurement and OHTS criteria as follows: group 1 with CCT<555 μm; group 2 with CCT 555-584 μm; and group 3 with CCT≥585 μm. Correlation analysis was performed to compare the 2 devices; paired sample t test, Bland and Altman analysis were used.
Results: The mean IOP levels measured by rebound tonometer and GAT were 13.9±2.3 and 13.5±2.5 mm Hg in Group1 (p=.587), 15.76±2.7 and 15.3±3.1 mmHg in Group 2 (p=.563), and 17.76±2.6 and 18.42±3.03 mm Hg in Group 3 (p=.878), respectively. Rebound tonometry and GAT readings were strongly correlated in terms of IOP measurement in all CCT groups (r=0.78, p<.0001).
Conclusions: The use of rebound tonometer is effective and safe in comparison to GAT readings. In eyes with a healthy cornea, the IOP measurements from the rebound tonometer and the GAT seemed to be similarly affected by CCT. Keywords : Intraocular pressure, Icare, rebound tonometry, Goldmann applanation tonometry, central corneal thickness