Academic Journal
Regional corneal epithelial thickness and asymmetry patterns in early keratoconus versus regular astigmatism using MS-39 anterior segment OCT: a comparative cross-sectional study.
| Τίτλος: | Regional corneal epithelial thickness and asymmetry patterns in early keratoconus versus regular astigmatism using MS-39 anterior segment OCT: a comparative cross-sectional study. |
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| Συγγραφείς: | Hadi Y; Eye Research Center, Five Senses Institute, Rassoul Akram Hospital, Iran University of Medical Sciences, Tehran, Iran., Kabood FK; Eye Research Center, Five Senses Institute, Rassoul Akram Hospital, Iran University of Medical Sciences, Tehran, Iran., Abdolalizadeh P; Department of Ophthalmology, School of Medicine, Urmia University of Medical Science, Urmia, Iran. paryaabdolalizadeh@gmail.com., Ghiasian L; Eye Research Center, Five Senses Institute, Rassoul Akram Hospital, Iran University of Medical Sciences, Tehran, Iran., Mazouchi M; Ophthalmic Research Center, Research Institute for Ophthalmology and Vision Science, Shahid Beheshti University of Medical Sciences, Tehran, Iran.; Bina Eye Hospital, Shahid Beheshti University of Medical Sciences, Tehran, Iran. |
| Πηγή: | BMC ophthalmology [BMC Ophthalmol] 2026 Oct 08; Vol. 26 (1). Date of Electronic Publication: 2026 Oct 08. |
| Τύπος έκδοσης: | Journal Article; Comparative Study |
| Γλώσσα: | English |
| Στοιχεία περιοδικού: | Publisher: BioMed Central Country of Publication: England NLM ID: 100967802 Publication Model: Electronic Cited Medium: Internet ISSN: 1471-2415 (Electronic) Linking ISSN: 14712415 NLM ISO Abbreviation: BMC Ophthalmol Subsets: MEDLINE |
| Imprint Name(s): | Original Publication: London : BioMed Central, [2001- |
| Ιατρικοί όροι (MeSH): | Keratoconus*/diagnosis , Keratoconus*/pathology , Tomography, Optical Coherence*/methods , Epithelium, Corneal*/pathology , Astigmatism*/diagnosis , Astigmatism*/pathology, Anterior Eye Segment/diagnostic imaging ; Humans ; Cross-Sectional Studies ; Female ; Male ; Adult ; Young Adult ; ROC Curve ; Adolescent ; Middle Aged |
| Περίληψη: | Background: To compare corneal epithelial thickness (CET) profiles among different types of regular astigmatism and early keratoconus (KCN) using the MS-39 anterior segment optical coherence tomography (AS-OCT) and to identify disease-specific epithelial asymmetry patterns, regional epithelial thickness, and ROC performance. Methods: This comparative cross-sectional study included 96 eyes from 55 participants: with-the-rule astigmatism (WTR, n = 34), against-the-rule astigmatism (ATR, n = 19), oblique astigmatism (OBL, n = 13), and early keratoconus (KCN, n = 30). Corneal epithelial thickness maps and central corneal thickness (CCT) were obtained with the MS-39 AS-OCT. Because some participants contributed both eyes and group sizes were unequal, eye-level comparisons used participant-clustered robust standard errors. Multivariable models additionally adjusted for age, sex, cylinder power, and CCT. ROC 95% confidence intervals were estimated by participant-level cluster bootstrap. Results: Regular astigmatic eyes showed the expected superior-to-inferior epithelial thickness gradient, whereas early KCN eyes showed relative superior epithelial thickening and attenuation of this gradient. CCT was lower in early KCN than in regular astigmatism (499.9 ± 29.3 μm vs. 555.7 ± 39.5 μm; P < 0.001). After adjustment for age, sex, cylinder power, and CCT, superior epithelial thickness remained greater in early KCN in the 2-5 mm annulus (adjusted B = + 2.78 μm; 95% CI, 1.15 to 4.41; P < 0.001) and 5-7 mm annulus (B = + 3.17 μm; 95% CI, 1.30 to 5.04; P < 0.001). The superior-inferior difference in the 2-5 mm zone also remained attenuated (B = + 2.10 μm; 95% CI, 0.51 to 3.68; P = 0.010). Superior ET at 2-5 mm had an AUC of 0.75 (95% CI, 0.62-0.87); a combined epithelial model yielded an AUC of 0.79 (95% CI, 0.67-0.90). Conclusions: Early KCN showed region-specific epithelial thickness differences characterized by relative superior epithelial thickening and attenuation of the normal vertical epithelial gradient. These differences persisted after adjustment for overall CCT, suggesting that the principal findings were not explained solely by differences in total corneal thickness. Diagnostic performance was moderate, so epithelial mapping should be considered an adjunct to established tomographic assessment. (© 2026. The Author(s).) |
| Competing Interests: | Declarations. Ethics approval and consent to participate: The Ethics Committee affiliated with Iran University of Medical Sciences in Tehran, Iran reviewed and approved the protocol of the study (IR.IUMS.FMD.REC.1402.272) in 2023. Consent for publication: Written informed consent was obtained from all participants. Competing interests: The authors declare no competing interests. |
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| Contributed Indexing: | Keywords: Anterior segment optical coherence tomography; Astigmatism; Corneal epithelial thickness; Keratoconus; Refractive surgery screening |
| Entry Date(s): | Date Created: 20261009 Date Completed: 20261009 Latest Revision: 20261011 |
| Update Code: | 20261011 |
| PubMed Central ID: | PMC13651415 |
| DOI: | 10.1186/s12886-026-05412-5 |
| PMID: | 42850600 |
| Βάση Δεδομένων: | MEDLINE |
| ISSN: | 1471-2415 |
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| DOI: | 10.1186/s12886-026-05412-5 |