Longitudinal changes in central corneal thickness and their relation to glaucoma status: an 8 year follow up study

Abstract

Aims: To determine if central corneal thickness (CCT) changes over time and if this change relates to glaucoma progression.

Methods: 39 patients (64 eyes) with open angle glaucoma, ocular hypertension, glaucoma suspect status, or a normal eye examination were examined at two visits. CCT, age, race, sex, family history of glaucoma, presence of diabetes and systemic hypertension, diagnosis, visual acuity, spherical equivalent, intraocular pressure, vertical and horizontal cup to disc ratios, number of glaucoma medications prescribed, Advanced Glaucoma Intervention Study (AGIS) score and mean deviation of Humphrey visual fields, and interventions required were recorded. Statistical analysis used the Wilcoxon signed ranks test, linear regression, and analysis of variance.

Results: Between the two visits (mean 8.2 years apart), mean CCT decreased by 17 μm in right eyes (p<0.002) and by 23 μm in left eyes (p<0.001). This decrease was greater in right eyes of patients with primary open angle glaucoma than in normals (p = 0.041). There was no significant association between change in CCT and other examination parameters. Change in CCT was not associated with topical carbonic anhydrase inhibitor use.

Conclusion: In this longitudinal study, CCT decreased over time, but this may not be related to glaucoma progression.