Purchase this article with an account.
Alexander Leube, Rajat Agarwala, Siegfried Wahl; Agreement and repeatability of the assessment of central corneal thickness using a novel optical coherence based biometer. Invest. Ophthalmol. Vis. Sci. 2019;60(9):2126.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
Central corneal thickness (CCT) plays an important role in the clinical ophthalmological practice, since the intraocular pressure, planning of refractive surgery procedures and intraocular lens calculations depend on it. Therefore, the current study investigated the agreement and repeatability of a novel optical coherence based biometer (OCB) in comparison to high resolution anterior optical coherence tomography (OCT).
A total of 27 subjects took part in the study with a mean age of 24±4 years. The mean spherical refractive error was -2.25 D for the right eye and -2.00 D for the left eye. CCT was measured three times using the OCB (IOL Master 700, Carl Zeiss Meditec AG, Jena, Germany) and the OCT (Cirrus HD-OCT 5000, Carl Zeiss Meditec AG, Jena, Germany) in both eyes of the participants, randomly. CCT values were automatically provided by the software of both devices. The data was evaluated using Bland-Altman analysis, to calculate the agreement by 1.96 times the standard deviation of the difference as 95% limits of agreement (95% LoA) for the inter-device comparison. The intraclass correlation coefficient (ICC) was computed to check for repeatability between the consecutive measurements for each device separately.
The mean CCT assessed from the right eye was 542.8 ± 28.1 µm and 538.7 ± 30.5 µm and from the left eye 541.2 ± 29.6 µm and 538.7 ± 30.1 µm for the OCB and the OCT method, respectively. Mean difference was 4.1 µm (p < 0.01) with 95% LoA from -9 µm to 17 µm in the right eye and mean difference was 2.5 µm (p = 0.02) with 95% LoA from -7.5 µm to 12 µm in the left eye. Test-retest assessment of CCT from both devices showed high repeatability (ICC > 0.94) and small mean differences (Δ < 0.9 µm) for the OCB and the OCT measurement.
The results depict a small statistical difference in the assessment of CCT between OCB and OCT. However, this difference is clinically insignificant for glaucoma diagnostics or laser in situ keratomileusis surgery since it ranges below 1% of total CCT. Thus, it can be concluded that the optical coherence biometer, which is simpler to use, provides precise and repeatable measures of the central corneal thickness instead of the optical coherence tomography in the clinical setting.
This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.
This PDF is available to Subscribers Only