Exploring corneal and anterior segment changes in asymptomatic vitamin B12 deficiency: a comparative observational study with negative findings
Abstract
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 comparative observational 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.
Keywords
Vitamin B12 deficiency, corneal topography, anterior segment parameters, specular microscopy, ocular imaging
Ethical Statement
References
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