Longitudinal Evaluation of Central Corneal Thickness in Ocular Hypertensive Patients

Abstract

Abstract: : Purpose: Central corneal thickness (cct) was reported to be increased in patients with ocular hypertension. Increased cct may lead to false high IOP readings. The purpose of our study was to find out if there are changes of cct with time in patients with ocular hypertension. Methods: We investigated 63 patients recruited from the European Glaucoma Prevention Study (EGPS) (mean age: 57±11years, 52% females, 48% males). Within the EGPS 1077 ocular hypertinsive patients were included and randomized to either treatment with topical dorzolamide or placebo (Ophthalmology 2002). Using ultrasonic pachymetry cct was evaluated at two different visits (mean time span between visits: 45±11 months). 81% of the measurements were performed am and 19% pm. In 9.5% of the patients the two measurements were on different times. All measurements were performed after visual field testing and tonometry. Results: Mean cct at the first visit was 575±39µm and at the second visit 582±38µm. This mean increase of cct (6±18µm) was statistically significant (p<0.01). In 17% of the cases cct increased more than 20µm. In 5% of the cases cct was decreased by more than 20µm. Conclusion: Central corneal thickness (cct) in patients with ocular hypertension may increase with time. This may be an effect of either age, treatment or disease or a combination of two or all of these. IOP also increases with age. It needs to be studied if this might be, in part, be explained by an increase of cct. As our sample size represents only 6% of the whole EGPS sample, generalization should be avoided.

Keywords: intraocular pressure