Abstract
Abstract: :
Purpose: Central Corneal Thickness (CCT) has been shown to be a significant and independent risk factor for the development of visual field defects in primary open–angle glaucoma (POAG). We looked to determine if there was a correlation between CCT and severity of visual field loss in a predominantly African–American glaucoma population. Methods: The charts of all patients with a diagnosis of POAG (365.11) seen in a one–month period were retrospectively reviewed. Patients who had a history of ocular surgery, corneal disease, with visual field loss from a non–glaucomatous etiology, and without pachymetry measurements were excluded. Patients were divided into three groups: thick corneas (CCT greater than 580 microns), average corneas (CCT between 501 and 579 microns), and thin corneas (CCT less than 500 microns). Visual fields were scored on a scale of increasing severity from 0–4 using a modified Hodapp–Anderson–Parrish criterion. Results: 56 patients met criteria. 10 patients had thick corneas, 29 had average corneas, and 17 had thin corneas. The average visual field score was 1.76 (SEM = 0.36) for the thin cornea group, 1.31 (SEM = 0.25) for the average cornea group, and 0.80 (SEM = 0.33) for the thick cornea group. There was no significant difference in age, number of years with glaucoma, and maximum IOP between groups. When patients were grouped according to visual field loss, those with more advanced visual field loss (scores of 3 or 4) had an average CCT of 514.5 microns versus those with less or no visual field loss (scores of 0,1, or 2) who had an average CCT of 532.1 microns. The thin cornea group was much more likely to have visual field loss at presentation (70.6%) than the thick and average groups (28.2%). Conclusions: CCT appears to be an important and relatively independent risk factor for the development of visual field loss in patients with POAG in an urban, predominantly African–American, glaucoma population.