Journal of Paramedical Sciences & Rehabilitation

Journal of Paramedical Sciences & Rehabilitation

Central corneal thickness, Normal limits, Refractive error, Glaucoma, Quantile regression model, Iran

Document Type : Original Article

Authors
N Nakhjavanpour 1
A Payandeh 1
H Ostadimoghddam 2, 3
F Doroodgar 4
1 Health Promotion Research Center, Zahedan University of Medical Sciences, Zahedan, Iran
2 Refractive Errors Research Center, School of Paramedical Sciences, Mashhad University of Medical Sciences, Mashhad, Iran
3 Department of Optometry,School of Paramedical Sciences, Mashhad University of Medical Sciences, Mashhad, Iran
4 Eye Research Center, Tehran University of Medical Sciences, Tehran, Iran
10.22038/jpsr.2017.21917.1561
Abstract
Purpose:
Central corneal thickness (CCT) as an anterior segment eye parameter, is an important factor for evaluation of patients with ocular disorders. The objective of this study was to Assessment of Age, Gender, and Refractive Errors on Central Corneal Thickness in Subjects Referring to Al-Zahra Eye Hospital of Zahedan using a robust statistical methodology.
Methods:
The present study was conducted on 755 eyes of qualified subjects referring to Al-Zahra eye hospital of Zahedan, the capital city of Sistan-and-Baluchestan provience from 2014 to 2016. After summarizing the data, linear quantile regression was fitted and normal values were estimated. SPSS (ver. 21) and R (3.3.0) were employed for analysis.
Results:
In this study, 422 subjects (56%) were female. Mean of age was 27±7.6 years old. According to the linear quantile regression model findings for subjects with a moderate CCT, age had a significant effect on CCT. Conversely, gender and spherical equivalence indicated no substantial effect on CCT. Normal limits of CCT were (489-602) µm and (482-600) µm for females and males, respectively. We also reported these limits by age and gender for comparisons.
Conclusion:
Normal limits of CCT can be used by ophthalmologists in examinations before refractive error operations and assessment of ocular pathologies like glaucoma.
Keywords
Central corneal thickness
normal limits
refractive error
glaucoma
quantile regression model
Iran
Subjects
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Journal of Paramedical Sciences & Rehabilitation
Volume 6, Issue 4
Autumn 2017
Pages 7-14