Tomographical Analyses of Cornea and Anterior Chamber in Eyes with Posterior Embryotoxon

Year 2025, Volume: 78 Issue: 4, 380 - 389, 31.12.2025

Burak Tanriverdi

https://doi.org/10.65092/autfm.1811927

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.

Ethical Statement

The study received ethical approval from the Lokman Hekim University Scientific Research Ethics Committee (Approval number: 2025/242).

Supporting Institution

None.

Posterior Embriyotokson'lu Gözlerde Kornea ve Ön Kamara Parametreleri'nin Tomografik Analizi

Abstract

Amaç: Refraktif cerrahi adaylarında posterior embriyotokson (PE) bulunan gözlerde ön ile arka korneal yüzey ve ön kamara parametrelerini değerlendirmek ve bu parametrelerin yaş, cinsiyet ve refraktif durum ile ilişkisini araştırmak.
Gereç ve Yöntem: Bu retrospektif, kesitsel çalışmaya 48 PE’li ve 50 kontrol göz dahil edilmiştir. Scheimpflug–Placido tomografi kullanılarak korneal keratometri, pakimetri, asferisite, elevasyon, kornea hacmi (KH), pupil ofset, yüksek-sıralı aberasyonlar (HOA’lar), nokta-saçılım fonksiyonu (NSF) ile ön kamara derinliği (ÖKD), hacmi (ÖKH) ve açısı (ÖKA) parametreleri analiz edilmiştir.
Bulgular: Ortalama yaş PE ve kontrol grupları arasında benzerdi (34,0±13,86 yıl - 30,0±5,87 yıl, p=0,618). Cinsiyet, ortalama refraksiyon kusuru ve görme keskinliği açısından gruplar arasında anlamlı fark bulunmamıştır (tümünde p>0.05). PE grubunda arka K1 değeri anlamlı düzeyde daha dik (p=0.036) ve KH daha yüksek bulunmuştur (p=0.046). ÖKD ve ÖKH PE grubunda anlamlı olarak daha düşük; nazal ve temporal ÖKA değerleri ise anlamlı düzeyde daha dardı (tümünde p<0.05). PE’li gözlerde kadınlarda, erkeklere kıyasla arka K1, K2 ve Kortalama değerleri daha dik; ön asferisite, pupil ofset, karekök-HOA ve koma değerleri daha yüksekti (tümünde p<0.05). Yaş ile arka K1, KH, ön kamara ve pakimetrik parametreler arasında negatif; ön K1 ve NSF arasında pozitif korelasyon saptandı (tümünde p<0.05). Sferik ekivalan, ön kamara parametreleri, pupil ofsetin y-bileşeni ve karekök-HOA değerleri ile negatif; pupil ofsetin x-bileşeni ile pozitif korelasyon gösterdi (tümünde p<0.05).
Sonuç: PE’li gözlerde normal gözlerle karşılaştırıldığında ön kamara yapısında belirgin ve arka korneada hafif değişiklikler gözlenmektedir. Yaş, cinsiyet ve refraktif durumdan etkilenebilen bu farklılıklar, klinik tanı, izlem ve cerrahi planlama açısından önem taşıyabilir.

Keywords

Posterior embriyotokson , kornea , ön kamara , topografi.

Ethical Statement

Bu çalışma Lokman Hekim Üniversitesi Bilimsel Araştırmalar Etik Kurul tarafından onaylanmıştır. (Onay no: 2025/242)

Supporting Institution

Yoktur.

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