The central and peripheral corneal thickness was measured in 209 normal eyes. The mean central thickness was 0.523 mm ± 0.039 (standard deviation [SD]). The mean peripheral thickness was 0.660 mm ± 0.076 (SD). There was no significant difference between right and left eyes, or between male and female corneas. There was no correlation between the refractive error and the central corneal thickness. No correlation was found between the amount of arcus senilis and the peripheral thickness. A significant thinning of corneal periphery and decrease in the ratio of peripheral to central thickness was evident after the patients were over 50 years of age.
Martola E, Baum JL. Central and Peripheral Corneal ThicknessA Clinical Study. Arch Ophthalmol. 1968;79(1):28-30. doi:10.1001/archopht.1968.03850040030009