Relationship between central epithelial thickness and central corneal thickness in healthy eyes and eyes after laser in situ keratomileusis

Session Details

Session Title: Anterior Segment Imaging I

Session Date/Time: Monday 24/09/2018 | 16:30-18:00

Paper Time: 17:33

Venue: Room A4

First Author: : D.Maltsev RUSSIA

Co Author(s): :    E. Kudryashova   A. Kulikov   A. Mareichev              

Abstract Details

Purpose:

Central epithelial thickness (CET) and central corneal thickness (CCT) are two of the most important parameters when characterizing corneal anatomy, and vary from 48 to 60 µm and from 415 to 695 µm, respectively, in healthy eyes. Nevertheless, details about the relationship between CCT and CET, to the best of our knowledge, have not been reported. The aim of this study was to evaluate the relationship between central epithelial and corneal thickness in healthy subjects. In order to demonstrate the clinical utility of the CET to CCT ratio, we also evaluated its change following laser in situ keratomileusis (LASIK).

Setting:

This single-center cross-sectional study was conducted at Military Medical Academy, St. Petersburg, Russia. The study was approved by the Ethics Committee of Military Medical Academy.

Methods:

In this study we included 150 patients (150 eyes) who underwent LASIK and 83 healthy subjects (83 eyes). To study changes of the CET and CCT following myopic LASIK, including their ratio, we examined patients one day (73 eyes) and one month (77 eyes) postoperatively. In all patients the CET and CCT were measured using anterior segment optical coherence tomography with Copernicus REVO on B-scans. Statistical analysis was performed using Spearman rank test, t-test and ROC-analysis.

Results:

In healthy subjects, CET positively correlated with CCT (r = 0.53, p < 0.001), the CET to CCT ratio being 0.100 ± 0.006. The CET to CCT ratio increased to 0.111 ± 0.009 (p < 0.001) and to 0.132 ± 0.021 (p < 0.001) one day postoperatively and one month, respectively. Area under curve for the CET to CCT ratio as a diagnostic criterion for previously performed myopic LASIK was 0.97 (sensitivity 93.5%, specificity 91.6%). At the same time, the sensitivity and specificity of CET was 75.3% and 81.9%, respectively, with the area under the curve of 0.84

Conclusions:

In healthy subjects, corneal epithelium contributes a mean of 10.0% of corneal thickness. The CET to CCT ratio has a highly predictive value for indication of previously performed myopic LASIK. It appears that clinical application of epithelial thickness measurement in a number of corneal diseses can be improved by adjusting the CET for CCT.

Financial Disclosure:

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