Abstract

Purpose: To determine the average central corneal thickness (CCT) in healthy Saudi adults and to analyze the variations based on gender, age, region, and refractive errors.

Methods: Cross-sectional study of average CCT of subjects between the ages of 20 - 40 who were randomly invited to participate at a gathering center in Riyadh, Saudi Arabia. Volunteers were excluded if they had corneal or ocular pathology, a history of ocular surgery or trauma, and contact lenses wear within 7 days of data collection. CCT was measured using Scheimpflug tomography. Statistical analysis was performed to determine any association of CCT with age, gender, refractive error, and geographic location. A P value less than 0.05 was considered statistically significant.

Results: A total of 379 subjects (755 eyes) with a mean age of 28.88 ± 5.77 years. More than half of the participants were females 244 (64.4%). The mean CCT was 544.32 ± 36.25 μm (range, 447 - 654 μm). CCT was statistically significantly influenced by age (P = 0.0001) where CCT was significantly lower as age increases. Although there was no statistically significant relationship between CCT and regions, nor refractive errors. A tendency toward thinner cornea in participants from north and west regions (P > 0.05) and among hyperopic eyes (P-value 0.06).

Conclusions: The average CCT in the healthy adult Saudi population was comparable to the regional and global averages. There was a significant negative association between age and CCT, where CCT values decrease with older ages. Hyperopic eyes, north and west regions have a tendency to a thinner CCT.

Keywords: Central Corneal Thickness; Pachymetry; Scheimpflug Tomography; Saudi Arabia

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