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Repeatability and reliability of semi-automated anterior segment-optical coherence tomography imaging compared to manual analysis in normal and keratoconus eyes

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Abstract

Purpose

To assess the repeatability and reliability of semi-automated EyeMark Python program measurements compared to manual ImageJ image processing of anterior segment-optical coherence tomography (AS-OCT) structures in healthy and keratoconus eyes.

Methods

Heidelberg AS-OCT was used to image 25 eyes from 14 healthy subjects and 25 eyes from 15 subjects with keratoconus between the ages of 20 and 80 years, collected prospectively, in this observational case–control study. Visual axis scan containing vertical fixation light beam was selected from the 15-line AS-OCT scan raster. Central corneal thickness (CCT), anterior corneal radius of curvature (ACRC), posterior corneal radius of curvature (PCRC), and truncated anterior vault (TAV) were measured using ImageJ software and the EyeMark Python program. MedCalc and R were used to calculate the intraclass correlation coefficient (ICC) and generate Bland–Altman plots (BAP).

Results

When comparing the measurements of CCT, ACRC, PCRC, and TAV between manual ImageJ analysis and the EyeMark Python program, ICC values were consistently greater than 0.9, indicating excellent agreement. BAPs comparing the ImageJ and Python measurements of anterior segment structures show no systematic proportional bias and the average differences were near zero and within 95% of the limits of agreement.

Conclusions

Semi-automated tools may provide the necessary efficiency for point-of-care quantitative corneal analysis of raw AS-OCT images. The semi-automated EyeMark Python program offers a repeatable and reliable tool compared to manual ImageJ analysis for measuring anterior segment structures from AS-OCT images among individuals with keratoconus.

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Funding

This research was funded in part by the Program for Research Initiated by Students and Mentors (PRISM), University of Maryland School of Medicine Office of Student Research.

This work was also supported by the University of Maryland, Baltimore, Institute for Clinical & Translational Research (ICTR) and the National Center for Advancing Translational Sciences (NCATS) Clinical Translational Science Award (CTSA) Grant No. IUL1TR003098. Dr. Alexander received funding support from Grant KL2TR003099 and K23EY032525.

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Authors and Affiliations

  1. Department of Neurology, University of Maryland, Baltimore, MD, USA

    Anna N. Lin

  2. Cole Eye Institute, Cleveland Clinic, Cleveland, OH, USA

    Isa S. K. Mohammed

  3. Department of Ophthalmology and Visual Sciences, University of Maryland Eye Associates, University of Maryland, Baltimore, MD, USA

    Wuqaas M. Munir, Saleha Z. Munir, Libby Wei & Janet L. Alexander

  4. Department of Ophthalmology, University of Texas Southwestern Medical Center, Dallas, TX, USA

    Snehaa Maripudi

  5. Department of Ophthalmology, University of Maryland School of Medicine, Baltimore, MD, 21201, USA

    Janet L. Alexander

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  1. Anna N. Lin
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  2. Isa S. K. Mohammed
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  3. Wuqaas M. Munir
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  4. Saleha Z. Munir
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  5. Snehaa Maripudi
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  6. Libby Wei
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  7. Janet L. Alexander
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Contributions

All authors contributed to the study concept and design. Material preparation, data collection, and analysis were performed by Anna Lin. Anna Lin prepared Figs. 1, 2 and all tables. Libby Wei prepared supplemental Figs. 1–4. The first draft of the manuscript was written by Anna Lin and all authors commented on previous versions of the manuscript. All authors read and approved the final manuscript.

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Correspondence to Janet L. Alexander.

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Lin, A.N., Mohammed, I.S.K., Munir, W.M. et al. Repeatability and reliability of semi-automated anterior segment-optical coherence tomography imaging compared to manual analysis in normal and keratoconus eyes. Int Ophthalmol 43, 5063–5069 (2023). https://doi.org/10.1007/s10792-023-02909-6

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