ESCRS - FP08.04 - Repeatability Of Epithelial Thickness Mapping In Normal And Keratoconus Eyes Using A Novel Hybrid Scheimpflug - Optical Coherence Tomography Device

Repeatability Of Epithelial Thickness Mapping In Normal And Keratoconus Eyes Using A Novel Hybrid Scheimpflug - Optical Coherence Tomography Device

Published 2026 - 44th Congress of the ESCRS

Reference: FP08.04 | Type: Free paper | DOI: 10.82333/ph1p-ak53

Authors: Dr Maximilian Friedrich* 1 , A/Prof. Victor Augustin 1 , Ms Julia Keim 1 , Ms Luisa Finken 1 , Ms Emilia Felter 1 , A/Prof. Hyeck-Soo Son 1 , A/Prof. Gerd Auffarth 1

1David J. Apple International Laboratory for Ocular Pathology and International Vision Correction Research Centre (IVCRC), Department of Ophthalmology,University of Heidelberg,Heidelberg,Germany

Purpose

A novel diagnostic device combining Scheimpflug and anterior-segment optical coherence tomography promises increased accuracy in corneal diagnostics. The aim of this study was to analyze the epithelial thickness measurement repeatability in healthy and keratoconus eyes and define severity-dependent thresholds.

Setting

Tertiary Eye Hospital.

Methods

This prospective, cross-sectional, observational, monocentric study included a total of 217 eyes of 217 subjects divided into a keratoconus group (166 eyes of 166 subjects) and a healthy control group (51 eyes of 51 subjects). Keratoconus diagnosis and stage was established using multimodal imaging. Three measurements were performed with the novel combined Scheimpflug and optical coherence tomography device (Pentacam Cornea OCT) on the same day. Repeatability coefficients (RC) with two-sided 95% confidence intervals (CI) were calculated for epithelial parameters. The repeatability was compared between groups and according to keratoconus severity and crosslinking status.

Results

The median repeatability of the epithelial thickness was slightly better in the healthy group (RC = 3.3) compared to the keratoconus group (RC = 3.9; p < 0.001) when the tear film was excluded. The overall median repeatability with (RC = 3.7) and without tear film (RC = 3.8) did not differ significantly (p > 0.05). Repeatability worsened significantly in severe keratoconus stages (p < 0.01), while crosslinking status had only a marginal effect.

Conclusions

The hybrid tomographic device demonstrated high intra-subject repeatability for epithelial thickness assessment in healthy and keratoconus eyes. Epithelial thickness may have the potential to be incorporated into established keratoconus scores in the combined system for a more comprehensive analysis.