Assessing progression limits in different grades of keratoconus from a novel perspective : precision of measurements of the corneal epithelium
(2024) In Eye and Vision 11(1).- Abstract
Background: To assess repeatability and reproducibility of corneal epithelium thickness (ET) measured by a spectral-domain optical coherence tomographer (SD-OCT)/Placido topographer (MS-39, CSO, Florence, Italy) in keratoconus (KC) population at different stages, as well as to determine the progression limits for evaluating KC progression. Methods: A total of 149 eyes were enrolled in this study, with 29 eyes in the forme fruste keratoconus (FFKC) group, 34 eyes in the mild KC group, 40 eyes in the moderate KC group, and 46 eyes in the severe KC group. Employing the within-subject standard deviation (Sw), test-retest variability (TRT), coefficient of variation (CoV), and intraclass correlation coefficient (ICC) to evaluate... (More)
Background: To assess repeatability and reproducibility of corneal epithelium thickness (ET) measured by a spectral-domain optical coherence tomographer (SD-OCT)/Placido topographer (MS-39, CSO, Florence, Italy) in keratoconus (KC) population at different stages, as well as to determine the progression limits for evaluating KC progression. Methods: A total of 149 eyes were enrolled in this study, with 29 eyes in the forme fruste keratoconus (FFKC) group, 34 eyes in the mild KC group, 40 eyes in the moderate KC group, and 46 eyes in the severe KC group. Employing the within-subject standard deviation (Sw), test-retest variability (TRT), coefficient of variation (CoV), and intraclass correlation coefficient (ICC) to evaluate intraoperator repeatability and interoperator reproducibility. Results: The repeatability and reproducibility of MS-39 in patients with KC were acceptable, according to ICC values ranging from 0.732 to 0.954. However, patients with more severe KC and progressive peripheralization of the measurement points had higher TRTs but a thinning trend. The current study tended to set the cut-off values of mild KC, moderate KC, and severe KC to 4.9 µm, 5.2 µm, and 7.4 µm for thinnest epithelium thickness (TET). When differences between follow-ups are higher than those values, progression of the disease is possible. As for center epithelium thickness (CET), cut-off values for mild KC, moderate KC, and severe KC should be 2.8 µm, 4.4 µm, and 5.3 µm. This might be useful in the follow-up and diagnosis of keratoconus. Conclusions: This study demonstrated that the precision of MS-39 was reduced in measuring more severe KC patients and more peripheral corneal points. In determining disease progression, values should be differentiated between disease-related real changes and measurement inaccuracies. Due to the large difference in ET measured by MS-39 between various stages of disease progression, it is necessary to accurately grade KC patients to avoid errors in KC clinical decision-making.
(Less)
- author
- organization
- publishing date
- 2024
- type
- Contribution to journal
- publication status
- published
- subject
- keywords
- Corneal epithelium thickness, Keratoconus, Precision, Progression limits
- in
- Eye and Vision
- volume
- 11
- issue
- 1
- article number
- 1
- publisher
- Springer Nature
- external identifiers
-
- pmid:38163895
- scopus:85181219694
- ISSN
- 2326-0254
- DOI
- 10.1186/s40662-023-00368-9
- language
- English
- LU publication?
- yes
- id
- b67796ee-e86e-4c4a-adc1-7819a6b1a4e5
- date added to LUP
- 2024-02-12 11:20:17
- date last changed
- 2024-04-14 02:51:22
@article{b67796ee-e86e-4c4a-adc1-7819a6b1a4e5,
abstract = {{<p>Background: To assess repeatability and reproducibility of corneal epithelium thickness (ET) measured by a spectral-domain optical coherence tomographer (SD-OCT)/Placido topographer (MS-39, CSO, Florence, Italy) in keratoconus (KC) population at different stages, as well as to determine the progression limits for evaluating KC progression. Methods: A total of 149 eyes were enrolled in this study, with 29 eyes in the forme fruste keratoconus (FFKC) group, 34 eyes in the mild KC group, 40 eyes in the moderate KC group, and 46 eyes in the severe KC group. Employing the within-subject standard deviation (S<sub>w</sub>), test-retest variability (TRT), coefficient of variation (CoV), and intraclass correlation coefficient (ICC) to evaluate intraoperator repeatability and interoperator reproducibility. Results: The repeatability and reproducibility of MS-39 in patients with KC were acceptable, according to ICC values ranging from 0.732 to 0.954. However, patients with more severe KC and progressive peripheralization of the measurement points had higher TRTs but a thinning trend. The current study tended to set the cut-off values of mild KC, moderate KC, and severe KC to 4.9 µm, 5.2 µm, and 7.4 µm for thinnest epithelium thickness (TET). When differences between follow-ups are higher than those values, progression of the disease is possible. As for center epithelium thickness (CET), cut-off values for mild KC, moderate KC, and severe KC should be 2.8 µm, 4.4 µm, and 5.3 µm. This might be useful in the follow-up and diagnosis of keratoconus. Conclusions: This study demonstrated that the precision of MS-39 was reduced in measuring more severe KC patients and more peripheral corneal points. In determining disease progression, values should be differentiated between disease-related real changes and measurement inaccuracies. Due to the large difference in ET measured by MS-39 between various stages of disease progression, it is necessary to accurately grade KC patients to avoid errors in KC clinical decision-making.</p>}},
author = {{Ning, Rui and Wang, Yiran and Xu, Zhenyu and Gustafsson, Ingemar and Li, Jiawei and Savini, Giacomo and Schiano-Lomoriello, Domenico and Xiao, Yichen and Chen, Aodong and Wang, Xiaoying and Zhou, Xingtao and Huang, Jinhai}},
issn = {{2326-0254}},
keywords = {{Corneal epithelium thickness; Keratoconus; Precision; Progression limits}},
language = {{eng}},
number = {{1}},
publisher = {{Springer Nature}},
series = {{Eye and Vision}},
title = {{Assessing progression limits in different grades of keratoconus from a novel perspective : precision of measurements of the corneal epithelium}},
url = {{http://dx.doi.org/10.1186/s40662-023-00368-9}},
doi = {{10.1186/s40662-023-00368-9}},
volume = {{11}},
year = {{2024}},
}