Acute Disseminated Encephalomyelitis

  • Etiology: immune mediated leukoencephalopathy / demyelination involving brain, may involve cord
  • Imaging: plaques shorter than two vertebral body segments, involve less than half cross-sectional area of cord, peripherally located in dorsal and lateral columns, variable enhancement, brain lesions also
  • Clinical: seen post-viral infection (measles or influenza) or post-vaccination (10%), transient, monophasic, responds to steroids, associated with Ebstein Barr virus / cytomegalovirus / mycoplasma pneumonia

Radiology Cases of Acute Disseminated Encephalomyelitis

MRI of acute disseminated encephalomyelitis / ADEM
Axial FLAIR MRI of the brain (upper and lower left) show multiple high signal intensity lesions primarily in the white matter as well as in the medulla that enhance on T1 MRI with contrast (upper right). Sagittal T2 MRI without contrast of the cervical spine (below right) shows high signal intensity expansile lesions in the spinal cord from C2 to C7 as well as from T2 to T3.