Diurnal Variations In Corneal Thickness And Keratometry In Healthy Eyes: A Sector-Based Analysis Of Lifestyle-Related Factors
Published 2026 - 44th Congress of the ESCRS
Reference: POANT031 | Type: Poster | DOI: 10.82333/0jrt-4451
Authors: Dr David Pablo P Pinero* 1 , Mrs Laura Barberán Bernardos 1 , Dr Miguel Angel Ariza-Gracia 2 , Dr Philippe Büchler 2 , Dr Alberto Artola 3
1Optics, Pharmacology and Anatomy,University of Alicante,Alicante,Spain, 2ARTORG Center for Biomedical Engineering Research,University of Bern,Bern,Switzerland, 3Ophthalmology,Vithas Medimar International Hospital,Alicante,Spain
Purpose
To analyze diurnal variations in corneal thickness and curvature of the anterior and posterior corneal surfaces in healthy eyes, and to investigate the correlation between these changes and lifestyle habits
Setting
Optometric Clinic. University of Alicante, Alicante, Spain
Methods
A prospective observational study was conducted including 109 eyes from 55 healthy subjects. Corneal parameters were measured at five time points over a 10-hour period (9:00 a.m. to 7:00 p.m., every 2.5 hours). Intraocular pressure, corneal thickness, volume, and keratometry were measured. Anterior and posterior keratometry were analyzed globally and by sector using 1-mm radial rings. Lifestyle habits were recorded through morning and evening questionnaires. Diurnal changes were analyzed using repeated-measures ANOVA or Friedman tests, and correlations were assessed using Spearman’s rank correlation coefficient.
Results
Significant diurnal decreases were observed in IOP, central and minimum corneal thickness, and corneal volume (p ≤ 0.031). Anterior keratometry showed statistically significant but clinically negligible changes, predominantly in the inferotemporal region, while posterior keratometry remained stable throughout the day. Sector-based analysis revealed non-uniform spatial patterns of anterior curvature change, mainly within the central 4 mm. Weak to moderate positive correlations were found between water and coffee intake, smoking status, and changes in corneal thickness and volume. No relevant correlations were observed between lifestyle factors and keratometric parameters
Conclusions
Corneal thickness and volume exhibit significant diurnal decreases in healthy eyes, whereas anterior keratometric changes are minimal and clinically irrelevant when assessed globally. Sector-based analysis reveals localized anterior corneal changes, particularly in central and inferotemporal regions. Lifestyle factors such as hydration, caffeine intake, and smoking appear to modulate corneal thickness. These findings underscore the importance of considering time of day and behavioral factors when interpreting corneal measurements in both clinical and research settings