Spine MR imaging features of subacute combined degeneration patients

Subacute combined degeneration (SCD) is a potentially reversible neurological complication of a vitamin B12 deficiency; therefore, timely diagnosis and appropriate treatment are of great importance. The study was to evaluate the spine MR imaging features of SCD in a series of patients. Eight patients diagnosed with SCD from 2008 to 2010 comprised the study population. Spine MRIs were available for all eight patients, and three of them had follow-up MRIs after vitamin B12 treatment. Two radiologists evaluated the prevalence of signal intensity abnormality of spinal cord and analyzed the distribution and pattern of the signal change in consensus. And they also evaluated post-treatment MRI to find interval change. Seven of eight patients showed abnormal hyperintensity within posterior aspect of spinal cord on T2-weighted images. The spinal cord abnormalities were seen at cervical spine in five patients (62.5 %) and at thoracic spine in the other two patients (25 %). For patients with cervical spinal cord abnormalities, axial T2-weighted images showed symmetric linear T2-hyperintensity as an "inverted V" at cervical spinal cord. For patients with thoracic spinal cord abnormalities, the abnormal signal intensity looked bilateral paired nodular T2-hyperintensity as "dumbbell" or "binoculars" at thoracic spinal cord. Follow-up MRIs after vitamin B12 treatment showed interval resolution of the areas of abnormal T2-hyperintensity in all. Symmetric T2-hyperintensity within dorsal column of spinal cord is commonly seen in SCD patients with a linear pattern in the cervical spine and a nodular pattern in the thoracic spine.