Investigation of the Effect of Chronic Obstructive Pulmonary Disease on Corneal Transparency and Endothelial Characteristics: Cross-Sectional Study

Objective: In this study, it was aimed to investigate corneal transparency and endothelial characteristics of patients with chronic obstructive pulmonary disease (COPD) and compare these findings with ageand gender-matched healthy controls. Material and Methods: Forty-nine eyes of 49 patients with COPD (24 females, 25 males) and 65 eyes of 65 healthy controls (36 females, 29 males) were included in this study. Participants were evaluated using Scheimpflug corneal topography (Pentacam HR Oculus, Wetzlar, Germany) and specular biomicroscopy (Tomey, Nagoya, Japan) to obtain measurements of corneal pachymetry, keratometry, and densitometry values with corneal endothelial cell characteristics. Spirometry values [forced vital capacity (FVC), forced expiratory volume in 1 second (FEV1), and FEV1/FVC ratio], smoking status (pack-years), and disease duration were recorded in the patient group. Results: Corneal pachymetry and keratometry measurements were statistically similar in the study groups (p>0.05, for all). Although the measurement of endothelial cell count was lower in the patient group, it was not statistically significant (p=0.130). Higher corneal densitometry values were observed in the patient group compared to the control group in all depths and diameters (p<0.05, for all). Numerous corneal densitometry values in the patient group showed significant negative correlations with FVC measurements and positive correlations with smoking status (p<0.05, for all). Conclusion: It can be thought that corneal transparency can decrease throughout the entire cornea due to hypoxia in patients with COPD, and this effect is correlated with smoking status and disease severity. Therefore, patients with COPD should be evaluated carefully before ophthalmological procedures which can affect corneal transparency.