Correlation Between Intraocular Pressure and Central Corneal Thickness in Persian Children

Abstract

IntroductionThis study aimed to determine intraocular pressure (IOP) and central corneal thickness (CCT) measurements in healthy Persian children to find clinical reference values in this ethnicity. Additionally, we examined the possible relationship between these measurements.MethodsThis cross-sectional study included 262 eyes of 131 Persian primary school children between 6 and 13 years of age. All eyes were healthy and had no anterior or posterior segment abnormalities, corneal disease, or evidence of glaucoma. Specular microscopy was used to measure CCT and both noncontact tonometry (NCT) and Goldmann applanation tonometer (GAT) were used to measure IOP. Correlations between IOP measurements were also examined.ResultsMean CCT was 513.47 ± 34.51 μm in the right eye (OD) and 513.93 ± 33.88 μm in the left eye (OS). The CCT was not significantly different between older (10–13 years) and younger (6–9 years) patients. Mean IOP measured with GAT was 13.86 ± 2.13 mmHg OD and 13.72 ± 2.04 mmHg OS and mean IOP measured with NCT was 15.26 ± 2.38 mmHg OD and 15.11 ± 2.18 mmHg OS. The IOP and CCT measured with GAT were weakly correlated (OD: r = 0.141, P = 0.114; OS: r = 0.236, P = 0.007). However, IOP and CCT measured with NCT (OD: r = 0.487, P = 0.000; OS: r = 0.456, P = 0.000) were moderately correlated. Our outcomes demonstrated that for 100 μm increase in CCT, IOP measured with GAT and NCT increased by 0.8 and 3.3 mmHg, respectively, in OD and by 1.4 and 2.9 mmHg in OS. Based on intraclass correlation coefficients, IOP measurements made with GAT and NCT were in fair agreement in OD and in good agreement in OS.ConclusionThe IOP and CCT in healthy Persian school children (6–13 years old) were positively correlated. Our findings revealed that corneal thickness is thinner in Persian children than in most other racial groups.FundingThis study has been funded by deputy dean in research of School of Medicine and deputy vice chancellor of Shiraz University of Medical Sciences, Shiraz, Iran.

A comparison of NCT, Goldman application tonometry values with and without fluorescein

“…Stabuc Silih and Hawlina 21 also found no significant correlation between increased corneal thickness and GAT values. Nejabat et al 25 observed that NCT and GAT were correlated with CCT, although GAT values was lower than the NCT values. In the present study, we could not ascertain an increase in CCT with increasing nGAT and fGAT values.…”

Author’s Reply to Prevalence of Visual Impairment in School Children

“…Our article had just described the design, methods, eye examination techniques, and baseline characteristics of the participants. Although the two mentioned studies [2,3] were conducted on a small fraction of the same population, we did not find any scientific justifications to cite them in this publication. They might be cited in future articles from the Shiraz Pediatric Eye Study, if it was deemed necessary.…”

Central and peripheral corneal thickness in Malays and its variation with age

“…We did not measure intraocular pressure due to time constraints. Indeed intra ocular pressure has been shown to be correlated to CT 28 and it was found to be thinner in high myopia 29 . We have limited our participants to those with power ±3.00DS or less and cylindrical component of not more than 1.00DC to avoid the influence of refractive error on the CT measured.…”