Corrected Intraocular Pressure Variability with Central Corneal Thickness Measurement

Area of Science:

• Ophthalmology
• Biometry
• Corneal Physiology

Background:

• Intraocular pressure (IOP) is a key factor in glaucoma diagnosis.
• Central corneal thickness (CCT) is known to influence IOP measurements.
• Variability in CCT measurement techniques may affect IOP assessment.

Purpose of the Study:

• To compare intraocular pressure (IOP) variability using central corneal thickness (CCT) measurements from ultrasonic and optical methods.
• To evaluate the correlation between measured IOP and CCT-corrected IOP (IOPcc) obtained via different CCT measurement tools.

Main Methods:

• 46 healthy subjects underwent CCT measurement using ultrasonic pachymetry (CCT1) and anterior-segment optical coherence tomography (AS-OCT) (CCT2).
• Intraocular pressure (IOP) was measured using Goldmann applanation tonometry (GAT).
• Statistical analysis was performed to compare IOP values and assess correlations between CCT and IOPcc.

Main Results:

• No significant differences were found in IOP or CCT-corrected IOP (IOPcc1, IOPcc2) between the measurement methods.
• A significant negative correlation was observed between corrected IOP values and CCT measured by both ultrasonic and optical tools (P=0.004 and P=0.001, respectively).

Conclusions:

• Intraocular pressure is dependent on and positively correlated with central corneal thickness.
• The method used for CCT measurement (ultrasonic vs. optical) did not significantly impact the observed correlations.
• Corrected intraocular pressure demonstrates a negative correlation with both ultrasonically and optically measured central corneal thickness.