Table 3.
Radiological features of the main mimics of inflammatory myelopathies.
| Spinal cord lesion–Sagittal view | Spinal cord lesion–Axial view | Enhancement | Differential diagnosis | ||||||
|---|---|---|---|---|---|---|---|---|---|
| Length | Location | Aspect | Location | Aspect | Inflammatory mimic | Diagnostic pitfalls | Other clinical clues to diagnosis | ||
| Spinal cord infarction | Variable | Cervical or thoracic | Linear “pencil-like”; restricted diffusion; vertebral body infarct in 10%; | Central or anterior | T2-hyperintensity of the anterior horn cells (owl or snake-eye sign) or H sign; concomitant vertebral artery occlusion | Owl or snake-eye sign; linear strip of anterior enhancement | AQP4+NMOSD | Bright(er) spotty lesions; Owl or snake-eye sign | Hyperacute presentation with flaccid paraparesis preceded by back pain |
| MOGAD | H-sign; linear aspect | ||||||||
| Nutritional deficits (B12, copper) | Long | Cervical or thoracic | Linear dorsal cord | Peripheral | Tract-specific | Usually absent | Paraneoplastic myelopathies | Long tractopathy | Progressive course; lack of gadolinium enhancement |
| Spondylotic myelopathy | Variable | Cervical | Fusiform spindle-shaped | Central | Nonspecific | Transverse band of flat pancake enhancement; involving the periphery and sparing the gray matter; slow resolving enhancement after treatment |
Nonspecific (inflammatory myelopathy) | Presence of enhancement | Progressive course |
| Spinal DAVF | Long | Thoracic, conus | Homogeneous hyperintensity centrally located; serpentine/ dilated veins/flow voids | Central | T2-hypointense flow voids along conus/cord surface; parenchymal T2-hyperintense signal sparing periphery | Patchy, homogeneous with an area of lack of enhancement “missing piece sign”, or absent enhancement; enhancement of large veins |
Progressive MS | Progressive course | Progressive course; worsened with Valsalva and steroids |
| MOGAD, AQP4+NMOSD | Conus involvement; long lesion | ||||||||
| Spinal ependymoma | Long | Cervical or thoracic, conus | Cord swelling, regular margins; rostral or caudal cyst; T2-hypointense rim, cap sign | Central | Nonspecific | Homogeneous non-specific | AQP4+NMOSD, sarcoidosis | Long lesion with cord swelling | Progressive course |
| Spinal astrocytoma | Long | Cervical or thoracic, conus | Cord swelling, irregular margins | Peripheral | Excentric with irregular margins and edema | Heterogeneous or no enhancement | MOGAD | Pediatric age, conus involvement | Progressive course |
| Spinal metastases | Variable | Cervical or thoracic | T2-hyperintensity largely exceeding the enhancing area | Central or peripheral | Nonspecific | Rim and flame sign: ring enhancement surrounding a region with fainter contrast-enhancement, flame-shaped appearance of enhancement rostral or caudal to the rim; dot sign: punctate enhancement in the center of the lesion on axial view | AQP4+NMOSD | Enhancement pattern similar to the ring-elongated | Known system cancer |
Only typical findings are reported.
AQP4+NMOSD, aquaporin-4-IgG-positive neuromyelitis optica spectrum disorders; DAVF, dural arteriovenous fistula; GFAP, glial-fibrillary acidic protein; MOGAD, myelin oligodendrocyte glycoprotein antibody-associated disease; MS, multiple sclerosis.