Association Between Central Corneal Thickness and Intraocular Pressure in Patients with Refractive Anomalies and Emmetropes

Mimoza Ismaili

International Journal of Biomedicine. 2023;13(3):91-95.
DOI: 10.21103/Article13(3)_OA6
Originally published September 5, 2023


Background: The aim of this study was to determine the relationship between central corneal thickness (CCT) and intraocular pressure (IOP) in patients with refractive anomalies and emmetropes.
Methods and Results: This retrospective study was conducted in the Department of Ophthalmology at the University Clinical Center. The study included 330 respondents, with a total of 660 eyes, divided into two groups. The test group (TG) included 180 respondents with refractive anomalies (65 respondents with hypertropia, 65 with myopia, and 50 with astigmatism); the control group (CG) included 150 respondents with uncorrected visual acuity – 6/6 in both eyes. All respondents included in the research were aged 18–40, with an average age of 22.9 years. The values of CCT in TG was around 499.3–577.1 μm. From 360 eyes in the TG with refractive anomalies, the highest IOP values were found in the astigmatic group (20.6 mmHg) and the lowest values in the myopic group (15.3 mmHg) (P<0.001) and were statistically higher compared to the CG (P<0.001 in both cases).
We found a statistically significant, moderate positive correlation between the values of CCT and IOP in the hypermetropic group (rs=0.655, 95% CI: 0.540 to 0.745, P<0.0001) and a statistically significant low negative correlation (rs=-0.209, 95% CI: -0.373 to -0.033, P=0.0165) between the values of CCT and IOP in the myopic group. Also, a statistically significant low negative correlation (rs=-0.304, 95% CI: -0.510 to -0.152, P=0.0005) was found between the values of CCT and IOP in the astigmatism group.
Conclusion: The results of our study show that increasing the CCT values in the hypermetropic group leads to an increase in the IOP values. Therefore, these findings can be used as a reference for our population, which would assist in the early diagnosis of ocular hypertension.

central corneal thickness • refractive anomaly • intraocular pression
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Received May 16, 2023.
Accepted June 10, 2023.
©2023 International Medical Research and Development Corporation.