Journal of Ophthalmic and Vision Research
ISSN: 2008-322X
The latest research in clinical ophthalmology and the science of vision.
In Vivo Intraocular Lens Thickness Measurement and Power Estimation Using Optical Coherence Tomography
Published date: Aug 09 2022
Journal Title: Journal of Ophthalmic and Vision Research
Issue title: July–Sep 2022, Volume 17, Issue 3
Pages: 353–359
Authors:
Abstract:
Purpose: To estimate the power of an implanted intraocular lens (IOL) by measuring IOL thickness using anterior segment optical coherence tomography (AS-OCT) and to assess the repeatability of measurements.
Methods: Ninety-seven eyes were studied one month after uneventful phacoemulsification within the bag Acrysof SA60AT IOL implantation (range +11 to +35). All eyes had postoperative refraction of ±0.5 D of target refraction. AS-OCT was used to measure the central thickness of the IOL. Correlation between labelled IOL power and central IOL thickness as well as the measure of repeatability, for example, intraclass correlation coefficient (ICC), were evaluated. IOL thicknesses were also calculated using a formula and compared with AS-OCT-derived measurements.
Results: IOL thickness correlated significantly with labelled IOL power (R2 = 0.985, P < 0.001). The regression equation (IOL Power = [0.04 × IOL thickness in micron] – 7.56) indicates 25 microns of central IOL thickness change per 1D power change. Over the studied range, IOL power could be estimated with a precision of 0.85 ± 0.02 D (95% confidence interval: 0.83–0.94D). ICC for repeated measurements was 0.999. There was a significant correlation between calculated and measured (AS-OCT) IOL thickness (R2 = 0.984, P < 0.001).
Conclusion: Central IOL thickness measurements with the AS-OCT are highly repeatable and closely correlated with the labelled IOL power, which can predict the IOL power with ±0.85 D from the actual power. This method can be helpful in cases of postoperative IOL surprise.
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