(BQ) Part 2 book "Spine imaging - A Case-Based guide to imaging and management" presentation of content: Metabolic and demyelinating, congenital and genetic conditions, vascular, miscellaneous, signs in radiology. | Chapter 47 Anant Krishnan and Richard Silbergleit History ▶ A 32-year-old female presents with progressive sensory myelopathy (Figures , , , and ). Figure Figure Figure Figure 175 Chapter 47 Subacute Combined Degeneration of the Spinal Cord Findings Subacute degeneration of the spinal cord (SCD) from B12 deficiency. Sagittal T2-weighted images (Figures and ) and axial T2-weighted images (Figures and ) of the cervical and thoracic spine demonstrate a T2 hyperintense signal (arrows) extending craniocaudally along the dorsal aspect of the spinal cord. On the axial views, bilateral involvement of the dorsal columns of the spinal cord is seen. Figure Figure Figure Figure A workup was performed demonstrating abnormally low serum B12 levels of 103 pg/ml (normal range = 271–870 pg/ml) and elevated serum methylmalonic acid of µmol/L (normal range ≤ ). Mean corpuscular volume (MCV) was high and red blood cell count (RBC) was decreased at Tril/L. On this basis, a diagnosis of vitamin B12-deficient SCD was made. Differential Diagnosis ▶ Other causes of SCD such as nitrous oxide inhalation have similar imaging features. A clinical history of nitrous oxide inhalation during surgery, dental work, or from recreational reasons, and related laboratory findings help separate this entity. ▶ HIV vacuolar myelopathy can closely mimic SCD imaging, but may also be associated with cord expansion. A potential cause is viral interruption of the methylation pathway leading to a similar clinical, radiological, and pathological end result. Cerebrospinal fluid (CSF) testing and blood work are also helpful in HIV and other infectious etiologies. 176 ▶ Copper deficiency myeloneuropathy. Copper deficiency is a cause of neurological dysfunction and can present with sensory ataxia, myelodysplastic syndrome, and anemia. Some patients demonstrate imaging findings very similar to SCD .
