Tomographical Analyses of Cornea and Anterior Chamber in Eyes with Posterior Embryotoxon
Abstract
Objectives: To evaluate anterior and posterior corneal surface and anterior chamber parameters in eyes with posterior embryotoxon (PE) among refractive surgery candidates, and to investigate their associations with age, gender, and refractive status.
Materials and Methods: This retrospective, cross-sectional study included 48 eyes with PE and 50 control eyes. Corneal keratometry, pachymetry, asphericity, elevation, corneal volume (CV), pupil-offset, higher-order aberrations (HOAs), point-spread function (PSF), and anterior chamber depth (ACD), volume (ACV), and angle (ACA) parameters were analyzed using Scheimpflug–Placido tomography.
Results: The mean age was similar between PE and control groups (34.0±13.86 years vs. 30.0±5.87 years, p=0.618). The gender and mean refractive error and visual acuity were comparable between groups (p>0.05 for all). The PE group exhibited significantly steeper posterior K1 (p=0.036) and greater CV (p=0.046). The ACD and ACV were significantly lower, and both nasal and temporal ACAs were significantly narrower in PE eyes (p<0.05 for all). Among PE eyes, females showed steeper posterior K1, K2, and Kmean, higher anterior asphericity, pupil-offset, root-mean-square of HOAs (RMS-HOAs), and coma values than males (p<0.05 for all). Age was negatively correlated with the posterior K1, CV, anterior chamber, and pachymetric parameters and positively with the anterior K1 and PSF (p<0.05 for all). Spherical equivalent was negatively correlated with the anterior chamber parameters, y component of the pupil-offset, and RMS-HOAs, while it positively correlated with x-component of the pupil-offset (p<0.05 for all).
Conclusion: Eyes with PE demonstrate distinctive anterior chamber and subtle posterior corneal alterations compared with normal eyes. These differences, influenced by age, gender, and refractive status, may have clinical relevance for diagnosing, monitoring, and surgical planning.
Keywords
Posterior embryotoxon, cornea, anterior chamber, topography.
Supporting Institution
None.
Ethical Statement
The study received ethical approval from the Lokman Hekim University Scientific Research Ethics Committee (Approval number: 2025/242).
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