Comparison Of Corneal Epithelial Thickness Measurement Between Ms-39 Oct And Insight 100 Very High-Frequency Digital Ultrasound
Published 2024 - 42nd Congress of the ESCRS
Reference: FP16.07 | Type: Free paper | DOI: 10.82333/e9mm-9y10
Authors: Timothy Archer* 1 , Dan Reinstein 2 , Radu Cucu 3 , Ruchi Gupta 1 , Joseph Potter 1
1Reinstein Vision,London,United Kingdom;London Vision Clinic,London,United Kingdom, 2Reinstein Vision,London,United Kingdom;London Vision Clinic,London,United Kingdom;Columbia University Medical Center,New York,United States;Sorbonne Université,Paris,France;Biomedical Science Research Institute, Ulster University,Coleraine,United Kingdom, 3Optana GmbH,Grossostheim,Germany
Purpose
To compare measurements of corneal epithelial thickness using MS-39 optical coherence tomography (OCT) and Insight 100 very high-frequency digital ultrasound (VHFDU).
Setting
London Vision Clinic, London, UK
Methods
This was a retrospective analysis of 100 virgin corneas (50 patients) that had corneal epithelial thickness measurement with MS-39 OCT (CSO Italia) (tear film included) and Insight 100 VHFDU (ArcScan Inc) (tear film excluded) performed on the same day. Data for left eyes were reflected in the vertical axis and superimposed onto the right eye values so that nasal/temporal characteristics could be combined. Averages were calculated for the central 2-mm diameter zone and for two concentric annuli of 2-5 mm diameter and 5-6 mm diameter, each divided into eight sectors. Agreement was analyzed by mean difference (OCT-VHFDU), 95% limits of agreement (LoA) (1.96 standard deviation), and Bland-Altman analysis.
Results
Mean central 2-mm zone epithelial thickness was 55.1±3.68 μm (range: 49 to 65 μm) with OCT and 54.2±3.29 μm (range: 44 to 64 μm) with VHFDU. Mean difference between devices for the central 2-mm zone was +0.88 μm (95% LoA of ±4.57 μm, P < .001). For the 8 sectors in the 2-5 mm annulus, the mean difference ranged from +0.27 μm (infero-temporal zone, p=.23) to +1.72 μm (supero-nasal zone, p<.001) and the 95% LoA was between 4.04 μm and 4.54 μm. For the 8 sectors in the 5-6 mm annulus, the mean difference ranged from +0.79 μm (infero-temporal zone, p<.001) to +2.59 μm (supero-nasal zone, p<.001) and the 95% LoA was between 4.44 μm and 5.75 μm.
Conclusions
Corneal epithelial thickness measurements using MS-39 OCT were found to be slightly thicker on average than for Insight 100 VHFDU. The difference was greatest in the supero-nasal region and least in the infero-temporal region.