THE INFLUENCE OF CENTRAL CORNEAL THICKNESS ON INTRAOCULAR PRESSURE, MEASURED BY DIFFERENT TONOMETERS: NONCONTACT AND GOLDMANN APPLANATION TONOMETERS

Abstract

Aim: The aim of this study is to determine if the central corneal thickness (CCT) influences the concordance of intraocular pressure (IOP) readings taken with a noncontact tonometer (NCT) and a Goldmann applanation tonometer (GAT).

Methodology: 100 patients were enrolled in the present cross sectional comparative study. The difference in IOP readings between the 2 methods (NCT-GAT), were calculated and the relationship between the IOP readings, and CCT was analysed using a linear regression line.

Results: IOP measured by both NCT and GAT was significantly correlated with CCT. NCT readings were significantly higher in the thicker group (CCT>or=530 micron) than in the thinner group (CCT<530 microm). GAT readings had no difference between the thicker and thinner groups. An IOP value measured by NCT had a significant positive correlation with CCT .The value of IOP measured by NCT was significantly higher in the thicker group than in the thinner group.

Conclusion: NCT can be more affected by CCT than GAT.Therefore CCT can influence the discordance of IOP readings taken with NCT significantly, whereas only minor influence is observed with GAT.