ESCRS - FP31.06 - Systematic Detection Of Keratoconus In Optical Coherence Tomography

Systematic Detection Of Keratoconus In Optical Coherence Tomography

Published 2023 - 41st Congress of the ESCRS

Reference: FP31.06 | Type: Free paper | DOI: 10.82333/e7m6-2845

Authors: Suphi Taneri* 1 , Burcu Yücekul 2 , Anika Förster 3 , H. Burkhard Dick 4

1Eye Department at St. Franzis Hospital,Center for Refractive Surgery,Münster,Germany;Ruhr-University Bochum,Bochum,Germany, 2Department of Ophthalmology,Haseki Training and Research Hospital,Istanbul,-, 3Eye Department at St. Franzis Hospital,Center for Refractive Surgery,Münster,Germany, 4Ruhr-University Bochum,Bochum,Germany

Purpose

To detect keratoconus only by analyzing the corneal and epithelial map parameters and patterns in optical coherence tomography (OCT).

Setting

Tertiary care refractive surgery center 

Methods

Retrospective data collection. Corneal and epithelial thickness maps of normal, manifest and subclinical keratoconic eyes (according to the Belin-Ambrosio display, Pentacam, Oculus) were evaluated by OCT (Zeiss Cirrus 5000 HD). A novel two-step decision tree was developed based on previous studies with another OCT. In the first step, if at least one of the four independent parameters (pachymetry minimum, pachymetry minimum-median, pachymetry superonasal-inferotemporal, epithelial superonasal-inferotemporal) overrun the cutoff values, the eye was suspicious for keratoconus. In the second step, if epithelial map showed concentric thinning and the thinnest point of the cornea and epithelium is coincident, the eye was classified as keratoconic.

Results

The study included 172 manifest keratoconic eyes (108 patients), 21 subclinical keratoconic eyes (20 patients), and 172 normal eyes (90 age-matched participants). Step 1 captured 100% of manifest and subclinical keratoconic eyes. Step 2 ruled out all suspicious but normal cases and falsely, 2 subclinical keratoconic eyes. Our two-step decision tree reached 100% specificity, 100% sensitivity in manifest keratoconus and 90.4% sensitivity in subclinical keratoconus.

Conclusions

Pachymetric and epithelial map parameters and patterns in OCT can be used in the diagnosis of keratoconus, including subclinical cases, yielding a high level of agreement with a commonly used diagnostic reference, the Belin-Ambrosio display. Further improvements by refining our algorithm and including an automated evaluation in the software are desirable.