Analyses of Corneal Morphology of Patients with Obstructive Sleep Apnea

ABSTRACT

Purpose@#To analyze the relationship between corneal morphological factors and polysomnographic factors in patients with obstructive sleep apnea (OSA). @*Methods@#In all, 22 eyes of 22 patients with OSA were analyzed retrospectively under specular microscopy. The central corneal thickness (CCT), endothelial cell density (ECD), hexagonal cell percentage, and cell variation coefficient were measured using specular microscopy, and polysomnographic factors including the apnea-hypopnea index (AHI), respiratory disturbance index (RDI), oxygen desaturation index, and lowest O2 saturation were compared and analyzed between the OSA group and a control group consisting of 32 subjects. Additionally, we examined the statistical correlation between retinal nerve fiber layer (RNFL) thickness and the polysomnographic factors for the 12 OSA patients in which the RNFL thickness was measured. @*Results@#The mean CCT and mean ECD were significantly lower in the OSA group than in controls (p = 0.033, p = 0.021, respectively). As the severity of OSA worsened, a significant negative correlation developed, such that the CCT decreased as the AHI and RDI increased (r = -0.519, p = 0.013 and r = -0.542, p = 0.009, respectively); in addition, the ECD decreased as the RDI increased (r = -0.454, p = 0.034). As OSA progressed, the nasal RNFL thickness decreased with the lowest O2 saturation (r = 0.703, p = 0.011). @*Conclusions@#CCT and ECD were significantly lower in OSA patients than in controls and there was a significant correlation between corneal morphological factors and polysomnographic factors. Due to the possibility of hypoxia and various ophthalmic clinical diseases associated with OSA, close observation of ophthalmic abnormalities in OSA patients is required.