Correlation between changes and pattern of posterior retinal thickness distribution in patients with keratoconus

Abstract

Keratoconus is a progressive non-inflammatory, degenerative, and bilateral corneal disease. Despite studies of retinal abnormalities and changes in the posterior segment of patients with keratoconus, such as the RNFL, no comprehensive study has been performed on the changes and pattern of retinal thickness distribution in the posterior pole in patients with keratoconus. Therefore, we aimed to evaluate the retinal thickness changes in the posterior pole using OCT-PPAA in patients with keratoconus and compare the results with the comparison group. Methods: A total of 24 subjects with keratoconus (48 eyes) and 14 normal subjects (28 eyes) enrolled in this study. All subjects had anterior segment and posterior segment imaging. Posterior segment imaging by OCT included the PPAA map. Data were analyzed with multiple linear regression models and correlation tests to examine the mean and variance of the measured thickness of the retina and its distribution relative to the presence and severity of KCN.Statistical analysis was performed using SPSS software and P <0.05 was considered significant. Results: The posterior pole retinal thickness, both superior and inferior hemifields, as well as the overall retinal thickness in KCN patients was greater than the control group. There was a direct correlation between the overall retinal thickness of the posterior pole and the severity of KCN (R2 = 0.422, P<0.001). However, the variability of the retinal thickness showed no difference in between KCN-afflicted and healthy eyes.