Reliability Analysis Of Epithelial Thickness Measured By Anterior Segment Optical Coherence Tomography In Keratoconus Patients.
Published 2023 - 41st Congress of the ESCRS
Reference: PO0220 | Type: Free paper | DOI: 10.82333/p7w4-4z06
Authors: Jan Weindler* 1 , Tadas Naujokaitis 1 , Hyeck-Soo Son 1 , Maximilian Köppe 1 , Bogdana Kovalchuk 1 , Gerd Uwe Auffarth 1 , Ramin Khoramnia 1 , Victor Augustin 1
1Department of Ophthalmology,University of Heidelberg,Heidelberg,Germany
Purpose
Epithelial thickness analysis by anterior segment optical coherence tomography (AS-OCT) is a new corneal diagnostic procedure that may help to detect an early corneal ectasia. The aim of the study is to investigate the reliability of epithelial thickness parameters in patients with asymmetric keratoconus as well as healthy subjects using AS-OCT.
Setting
University Eye Clinic Heidelberg, Heidelberg, Germany
Methods
In this monocentric observational study 21 patients with very asymmetric ectasia (VAE; with significant keratoconus in one eye (VAE-KK) and normal tomography in the fellow eye (VAE-NT) and 21 healthy subjects (HS) were included. AS-OCT ANTERION (Heidelberg Engineering, Heidelberg, Germany) was used to measure the mean epithelial thickness, the standard deviation of the mean epithelial thickness, the minimum and maximum epithelial thickness, and the superior to inferior epithelial thickness difference. Three measurements were performed per eye. The standard deviation and coefficient of variation (CoV) were calculated. The repeatability of epithelial thickness measurements was compared in VAE-KK (n=21), in VAE-NT (n=21), and HS (n=21).
Results
Epithelial thickness was analyzed by AS-OCT in both eyes of patients with VAE and in one eye of HS. The mean epithelial thickness was 51µm in in HS, 51 µm in VAE-NT and 51 µm VAE-KK. The standard deviation of the mean epithelial thickness was 2 µm in HS, 2 µm in VAE-NT and 5 µm in VAE-KK. The minimum/maximum epithelial thickness was 44/57 µm in HS, 44/57 µm in VAE-NT and 39/61 µm in VAE-KK. The superior-inferior epithelial thickness difference was 2 µm in HS, 2 µm in VAE-NT and 1 µm in VAE-KK. The standard deviations and the median CoV of the evaluated epithelial thickness parameters were not statistically significantly different between the groups (p>0.05, Kruskal-Wallis test).
Conclusions
Epithelial thickness can be measured in keratoconus patients as well as healthy subjects by AS-OCT with high re-test reliability. Future studies should analyze if epithelial thickness analysis can support the early detection of corneal ectasia.