A 75-year-old woman was seen for evaluation of mild progressive loss of sensation in her hands and feet. Findings from neurological examination revealed a marked decrease in vibratory and position sense from her toes to her knees and in her distal fingertips. She also had diminished light touch over the same distribution. Her vitamin B12 level was 74 pg/mL (55 pmol/L). Magnetic resonance imaging of her cervical cord revealed increased T2 signal intensity from C1 to C5, and the abnormality was evident in the characteristic shape of the posterior columns (Figure, arrow). It is rare to see a magnetic resonance image correlate with vitamin B12 deficiency and even more so to see the abnormality so discreetly outline the posterior columns. This patient was treated with cyanocobalamin injections and experienced resolution of her symptoms over a 6-month period.
Okun MS, Vongxaiburana K, Valenstein E, Friedman W. Magnetic Resonance Imaging of the Posterior Columns in Vitamin B12 Deficiency. Arch Neurol. 2004;61(8):1321. doi:10.1001/archneur.61.8.1321