Evaluation of retinal nerve fiber layer and ganglion cell layer thicknesses with optical coherence tomography in patients with vitamin B12 deficiency

Aim: We aimed to compare the retinal nerve fiber layer (RNFL) and ganglion cell layer (GCL) thickness of B12 vitamin deficiency patients with healthy controls using optical coherence tomography (OCT). Methods: Forty-six patients (27 females / 19 males) diagnosed with B12 vitamin deficiency and 46 healthy controls (26 females / 20 males) with similar age and sex were included in the study. RNFL thickness of global, superotemporal, temporal, inferotemporal, superonasal, nasal and inferonasal sectors and GCL thickness and volume measurements of central, superior, inferior, temporal, and nasal sectors were performed using Spectralis-OCT device in all cases. Results: The mean age of the patient group was 42.17±15.34 years, while that of the control group was 44.21±12.34 years (p=0.528). Mean serum vitamin B12 levels were measured as 163,47±19,80 pg/ml in the patient group and 311,80±76,30 pg/ml in the control group (p <0,01). There was no statistically significant difference between the global RNFL thicknesses of the two groups (p> 0,05). However, statistically non-significant thinning was observed in the superotemporal and global RNFL thickness of the group with B12 vitamin deficiency (p values are 0,140 and 0,171, respectively). There was also no statistically significant difference between GCL thicknesses and volumes of the two groups (p> 0.05). Conclusions: No significant reduction was observed in RNFL and GCL thicknesses of adult subjects with B12 vitamin deficiency compared with healthy controls.