Correlation of corneal epithelial thickness with clinical severity of dry eye

Abstract

Background: Spectral-domain optical coherence tomography (OCT) has been used to measure corneal epithelium thickness in dry eye disease, allowing assessment of ocular-surface damage in different disease severity.Aim: This study aimed to determine the characteristics of corneal epithelial thickness with spectral-domain OCT in patients with dry eye and correlate epithelial thickness with the clinical severity.Setting: The study was conducted at outpatient clinic in the Department of Ophthalmology, Chulabhorn hospital, Bangkok, Thailand.Methods: It was a cross-sectional study and 92 dry eye patients were included. All participants were assessed using the dry eye questionnaire-5 (DEQ-5), tear film breakup time and fluorescein staining. Corneal epithelial thickness was measured with spectral-domain OCT. The mean and variance of epithelial thickness were calculated. Correlations of corneal epithelial thickness with other clinical parameters were calculated.Results: There were no statistical differences in corneal epithelium thickness between the non-severe and severe dry eye groups. The peripheral corneal epithelial thickness variance was significantly higher in the severe dry eye. There was a significant correlation between peripheral epithelial thickness variance and the clinical parameters.Conclusion: Peripheral corneal epithelial thickness variance was higher in the severe dry eye, suggesting that the peripheral ocular surface is more damaged. This also correlated with the symptoms and signs of dry eye, which can be used to assess the disease severity.Contribution: This study provided the correlation of corneal epithelial thickness measurement with spectral-domain OCT on the diagnosis of dry eye severities.