Exploring Corneal and Anterior Segment Changes in Asymptomatic Vitamin B12 Deficiency: A Cross-Sectional Study with Negative Findings

Öz

Purpose: To investigate whether vitamin B12 deficiency affects ocular anterior segment parameters including corneal endothelial cell characteristics and corneal topography in asymptomatic patients. Materials and Methods: This cross-sectional study included 45 patients with vitamin B12 deficiency (serum B12 level <200 ng/L) and 45 age- and sex-matched healthy controls. Specular microscopy was used to assess the corneal endothelial cell density, morphology, and central corneal thickness. Corneal topography parameters, such as minimum corneal thickness, epithelial and stromal thickness, keratometric values, and corneal elevation, were evaluated using the Sirius imaging system. Statistical comparisons were performed to identify differences between the groups. Results: There were no statistically significant differences between the vitamin B12 deficient and control groups in corneal endothelial cell density (2743±295 vs. 2859±212 cells/mm², p=0.09), average cell area, coefficient of variation, hexagonal cell ratio, or central corneal thickness (549.6±35.2 vs. 556.9±36.5 µm, p=0.34). Similarly, corneal topographic parameters, including minimum thickness, epithelial and stromal thickness, keratometric values, and anterior/posterior corneal elevations, showed no significant differences (all p>0.05). Although the difference in corneal endothelial cell density between the groups did not reach statistical significance (p=0.09), a trend toward lower cell density was observed in the vitamin B12 deficient group. Conclusion: In asymptomatic patients, vitamin B12 deficiency did not appear to cause significant alterations in corneal endothelial morphology or anterior segment parameters. However, further longitudinal studies with larger cohorts are needed to assess whether prolonged deficiency or additional ocular/systemic pathologies influence these ocular parameters.

Anahtar Kelimeler

• Vitamin B12 deficiency
• corneal topography
• anterior segment parameters
• specular microscopy
• ocular imaging

Etik Beyan

Ethics Committee Approval: AEŞH-BADEK1-2025-101, Ankara Etlik City Hospital Ethics Committee

Asemptomatik B12 vitamini eksikliğinde kornea ve ön segment değişikliklerinin incelenmesi: negatif bulgularla kesitsel bir çalışma

Öz

Amaç: Asemptomatik hastalarda, B12 vitamini eksikliğinin kornea endotelyal hücre özellikleri ve kornea topografisi dâhil oküler ön segment parametrelerini etkileyip etkilemediğini araştırmak. Gereç ve Yöntem: Bu kesitsel çalışmaya, B12 vitamini eksikliği olan (serum B12 düzeyi <200 ng/L) 45 hasta ve yaş ve cinsiyet açısından eşleştirilmiş 45 sağlıklı kontrol dâhil edildi. Kornea endotelyal hücre yoğunluğu, morfolojisi ve santral kornea kalınlığı speküler mikroskopi ile değerlendirildi. Minimum kornea kalınlığı, epitel ve stromal kalınlık, keratometrik değerler ve kornea elevasyonu gibi kornea topografi parametreleri Sirius görüntüleme sistemi kullanılarak ölçüldü. Gruplar arasındaki farkları belirlemek için istatistiksel karşılaştırmalar yapıldı. Bulgular: B12 vitamini eksikliği olan grup ile kontrol grubu arasında kornea endotelyal hücre yoğunluğu (2743±295’e karşı 2859±212 hücre/mm², p=0,09), ortalama hücre alanı, varyasyon katsayısı, hekzagonal hücre oranı veya santral kornea kalınlığı (549,6±35,2’ye karşı 556,9±36,5 µm, p=0,34) açısından istatistiksel olarak anlamlı bir fark bulunmadı. Benzer şekilde, minimum kalınlık, epitel ve stromal kalınlık, keratometrik değerler ve ön/arka kornea elevasyonlarını içeren kornea topografik parametrelerinde de anlamlı fark saptanmadı (tüm p>0,05). Gruplar arasındaki kornea endotelyal hücre yoğunluğu farkı istatistiksel anlamlılığa ulaşmamış olsa da (p=0,09), B12 vitamini eksikliği olan grupta hücre yoğunluğunda azalma eğilimi gözlendi. Sonuç: Asemptomatik hastalarda, B12 vitamini eksikliğinin kornea endotelyal morfolojisi veya ön segment parametrelerinde anlamlı değişikliklere yol açmadığı görülmüştür. Ancak, uzun süreli eksiklik veya ek oküler/sistemik patolojilerin bu oküler parametreleri etkileyip etkilemediğini değerlendirmek için daha geniş kohortlarda yapılacak ileriye dönük çalışmalara ihtiyaç vardır.

Anahtar Kelimeler

• B12 vitamini eksikliği
• kornea topografisi
• ön segment parametreleri
• speküler mikroskopi
• oküler görüntüleme

Etik Beyan

Etik Kurul Onayı: AEŞH-BADEK1-2025-101, Ankara Etlik Şehir Hastanesi Etik Kurulu

Kaynakça

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