The Intraocular Pressure Measured by Different Tonometers in Corneal Edema

The investigators conduct this study to access the effect of corneal edema (the investigators are particularly interested in those who have the clinical central corneal edema) on the variation of intraocular pressure values measured by 3 commercial-available tonometers compare to the current gold standard tonometer; Goldmann applanation tonometer.

Previous published articles reported on the effect of corneal edema on the accuracy of tonometry were performed in enucleated cadaver eyes, or contact lens-induced corneal edema eyes. Thus, it remains unclear as to how the clinical corneal edema that is found in routine clinical practice will affect the variation of intraocular pressure measurement using the standard Goldmann applanation tonometer and other more modern tonometers such as the dynamic contour tonometer, the iCare, and the Tonopen.