Correlating central corneal thickness and intraocular pressure in ocular hypertension and glaucoma
Jonathan G. Soriano, MD, Ma. Margarita L. Lat-Luna, MD, Patricia M. Khu, MD
Objective
This study determined the relationship between central corneal thickness (CCT) and intraocular pressure (IOP) among patients with ocular hypertension (OHT) and glaucoma.
Methods
Patients diagnosed with OHT and primary glaucoma were recruited from the Glaucoma Clinic of the University of the Philippines–Philippine General Hospital. All underwent a comprehensive eye exam including determination of CCT by ultrasonic pachymetry, measurement of IOP by Goldmann applanation tonometry, axial-length determination and anterior-chamberdepth measurement by biometry. Statistical analyses included chi square, Kruskal Wallis analysis of variance, Pearson correlation, and linear regression. A conversion factor for the corrected IOP was subsequently obtained.
Results
Eighty-three eyes of 47 patients were included. CCT was thickest among patients with OHT (588 µm), followed by primary open-angle glaucoma (538 µm), angle-closure glaucoma (531 µm), and normal-tension glaucoma (526 µm). A moderate positive correlation between CCT and IOP was seen among patients with OHT (r = 0.55, p = 0.04). An increase of 5.3 mm Hg per 100 µm increase in CCT was noted.
Conclusion
Central corneal thickness among Filipino patients with OHT was thicker than those with glaucoma. A direct correlation was seen between CCT and IOP of these patients.
Keywords: Central corneal thickness (CCT), Glaucoma, Pachymetry, Goldmann applanation tonometry (GAT)