Prevalence of MR imaging abnormalities in vitamin B12 deficiency patients presenting with clinical features of subacute combined degeneration of the spinal cord.

BACKGROUND AND AIMS: Subacute combined degeneration (SACD) of the spinal cord, characterized by degeneration of lateral and posterior columns, is often found in vitamin B12 deficiency. Our aim was to look for sensitivity of imaging in depicting the spinal cord abnormality in vitamin B12 deficient patients and to find any correlation of vitamin B12 levels with clinical scores/severity at time of presentation.

MATERIAL AND METHODS: A total 54 patients with biochemically proven vitamin B12 deficiency were included in the study. In all these patients MR study of cervico-dorsal spine was done. All the patients after initiation of appropriate treatment were followed up for a minimum of two months.

RESULTS: MRI showed cord signal abnormality in only 8 patients out of 54 patients with low sensitivity of 14.8%. After appropriate therapy, complete resolution of cord signal abnormalities was observed in all these 8 patients, on follow-up MR imaging. Significant negative correlation (r=-0.503, p<0.000) was seen between the clinical severity scores and initial vitamin B12 levels.

CONCLUSION: Conventional MRI may not be a useful tool for the diagnosis of SACD as it has very low sensitivity. Inverse correlation of Vitamin B12 levels with clinical scoring suggests that initial serum vitamin B12 levels may help in predicting the clinical severity.