TEMPORAL OPTIC DISC PALLOR IN VITAMIN B12 DEFICIENCY - A NEURO-OPHTHALMIC INDICATOR BEYOND HEMATOLOGICAL MARKERS

Vitamin B12 deficiency is commonly associated with megaloblastic anemia; however, neurological manifestations may occur independently of hematological abnormalities. Optic neuropathy due to Vitamin B12 deficiency typically presents with temporal optic disc pallor secondary to papillomacular bundle involvement. This retrospective observational study was conducted over one year and included 30 patients with laboratory-confirmed Vitamin B12 deficiency. Fundus photographs and complete blood count (CBC) reports were analyzed. Nineteen patients (63.3%) demonstrated temporal optic disc pallor, while eleven (36.7%) had normal optic discs. A considerable proportion of patients with temporal pallor had normal hemoglobin and mean corpuscular volume (MCV). No consistent correlation was observed between hematological parameters and optic nerve involvement. The findings suggest that normal hemoglobin and MCV do not exclude Vitamin B12–related optic neuropathy. Routine ophthalmic evaluation is recommended in all patients with suspected or confirmed Vitamin B12 deficiency.