In this study, we reviewed the imaging findings of 40 patients diagnosed with spinal cord compression. 

Compressive myelopathy results from external pressure on the spinal cord, which can be localized to the epidural, intradural extramedullary, or intramedullary spaces. Key imaging findings include effacement of epidural fat, displacement of the thecal sac, and spinal cord compression.

Epidural Causes

1. Degenerative Disease:

   • Disk Herniation: The most common cause of compressive myelopathy, often leading to cauda equina syndrome. MRI shows continuity between the herniated disk and the donor disk, with possible cord edema.

     

     Fig 1: Sagittal T2w image shows disc herniation causing compression of anterior thecal sac, spinal cord and causing spinal canal stenosis.

   • Spinal Canal Stenosis: Multifactorial degenerative changes cause narrowing of the spinal canal, leading to cord compression. MRI reveals an hourglass appearance of the spinal canal with CSF effacement.

     

     Fig 13: Sagittal T2W image shows decreased signal intensity of dorsal vertebrae and posterior longitudinal ligament hypertrophy
     

     Fig 14: Sagittal T2W image shows decreased signal intensity of cervical vertebrae and posterior longitudinal ligament hypertrophy causing spinal canal stenosis

2. Infectious Disease:

   • Epidural Abscess: Often secondary to spondylodiscitis, presenting as a T1-hypointense, T2-hyperintense collection with peripheral enhancement. Associated with spondylodiscitis and paravertebral muscle involvement.

     

     Fig 4: Sagittal T1W+Gd image(left) and STIR(right) images shows a hypointense collection showing peripheral rim enhancement causing compression of spinal cord---S/o epidural abscess
     

     Fig 5: Axial post contrast T1W image shows hypointense collection showing peripheral rim enhancement causing compression of spinal cord.

3. Vascular Disease:

   • Epidural Hematoma: Typically seen in patients on anticoagulation therapy or with coagulopathy. MRI shows a biconvex epidural collection with variable signal intensity depending on the age of the blood products.

     

     Fig 6: Sagittal T1W image shows a well defined hyperintense collection in epidural space causing compression of spinal cord--S/o hematoma
     

     Fig 7: Axial T1W+Gd shows peripheral enhancement.
     

     Fig 8: T2W image the lesion appears hypointense

4. Metastatic Disease:

   • Spinal Metastases: The spine is a common site for metastases, often leading to cord compression. MRI reveals T1-hypointense, T2-hyperintense lesions with variable enhancement. Contrast-enhanced MRI is essential for assessing the extent of disease.

     

     Fig 9: In a K/c/o prostate cancer patient complaining of back ache, T2W image shows multiple isointense lesions involving dorsal vertebrae causing spinal canal stenosis.

   • Schwannoma:
     

     Fig 10: Axial T1W+Gd image shows heterogenously enhancing dumbell shaped lesion in left neural foramina extending into spinal canal and causing spinal cord compression
     

     Fig 11: T2W image shows heterogeneously hyperintense lesion at the level of C5 .
     

     Fig 12: T1W image shows isointense lesion at the level of C5 .

5. Metabolic Disease:

   • Extramedullary Hematopoiesis: Associated with conditions like myelofibrosis and sickle cell anemia. MRI shows well-defined, lobulated epidural masses with T1 hypointensity and T2 hyperintensity.

     

     Fig 15: A 53-year-old man with β-thalassemia presented with lower extremity weakness. MRI of the thoracolumbar spine revealed multilevel lobulated T1-isointense and T2-hypointense, avidly enhancing soft-tissue masses in the posterior epidural space and bilateral paravertebral extrapleural masses, consistent with extramedullary hematopoiesis. Findings also included posterior epidural fat effacement, spinal cord displacement, and diffuse red marrow conversion indicated by decreased T1 and T2 bone marrow signal intensity.

Intradural Extramedullary Causes

1. Arachnoid Cyst: A CSF-filled cyst that displaces the spinal cord. MRI shows a well-circumscribed cystic structure with CSF signal intensity.

   

   Fig 16: A well defiend cystic lesion following CSF signal intensity in all pulse sequences is noted in spinal canal causing compression of cord at D8 level.

2. Infection:

   • Intradural Abscess: Rare but serious, often associated with Staphylococcus aureus or Mycobacterium tuberculosis. MRI reveals an elongated T2-hyperintense collection with peripheral enhancement.

3. Primary Tumors:

   • Meningioma: Typically located anterior to the spinal cord in the cervical spine and posterior in the thoracic spine. MRI shows a T1- and T2-isointense lesion with avid enhancement and a broad dural base.

     

     Fig 17: Sagittal T1W+Gd image shows a well-defined avidly enhancing lesion with broad base towards dura in the spinal canal causing spinal cord compression-Meningioma
     

     Fig 18: Coronal T1W+Gd image shows a well defined avidly enhancing lesion in the spinal canal causing spinal cord compression-Meningioma
     

     Fig 19: Well defined lesion in the intra dural extra Medullary location along the right side causing cord compression and displacement to the left. --meningioma

   • Schwannoma and Neurofibroma: Benign nerve sheath tumors, often with a "target sign" appearance on MRI. Schwannomas are encapsulated, while neurofibromas are intertwined with the nerve.

     

     Fig 20: In a 23yr old patient with k/c/o of neurofibromatosis-1 came to follow up show a heterogeneously hyperintense lesion in the intradural space causing spinal cord stenosis-neurofibroma.
     

     Fig 21: Sagittal T1W image shows A well defined round to oval intradural extramedullary isointense mass at the level of D12-L1 causing compression of cord at conus medullaris
     

     Fig 22: Sagittal T2W image shows A well defined round to oval intradural extramedullary hyperintense mass at the level of D12-L1 causing compression of cord at conus medullaris
     

     Fig 23: On post contrast the lesion is showing contrast enhancement----Schwannoma

4. Intradural Metastases: Often seen in lung, breast, and hematologic malignancies. MRI shows T1-hypointense, T2-hyperintense lesions with enhancement, typically located at the conus medullaris.

   

   Fig 24: Patient with K/c/o Anaplastic pleomorphic xanthoastrocytoma presented with neck pain, Post contrast sagittal image shows Intradural extramedullary enhancing masses at C6 (dorsally) causing spinal cord impression.

Intramedullary Causes

1. Intramedullary Tumors:

   • Ependymoma: The most common adult intramedullary tumor, often in the cervical cord. MRI shows a well-circumscribed, T2-hyperintense lesion with avid enhancement and polar cysts.

     

     Fig 25: Ependymoma- A large ovoid lesion appearing hyperintense T2 s is located at D11,D12 and L1 level It demonstrates vivid contrast enhancement.

   • Astrocytoma: Typically presents as a fusiform expansion of the cord with variable enhancement. Less sharply delineated than ependymoma.

     

     Fig 26: There is an expansile, T2-heterogenously hyperintense and T1 hypointense intramedullary lesion involving the pons, medulla oblongata and extending caudally into the cervical spinal cord from C1 to D4. The lesion demonstrates heterogeneous post-contrast enhancement with areas of cystic degeneration(not shown). There is associated perilesional edema and mild mass effect on the surrounding structures. No evidence of hemorrhage is seen. The imaging features are consistent with an astrocytoma.

   • Lipoma:

2. Intramedullary Metastases: Rare, often with extensive edema disproportionate to the lesion size. MRI shows enhancing intramedullary masses with peritumoral edema.

   

   Fig 27: a patient with metastatic lung cancer and known brain metastases who presented with progressive lower limb weakness. The image on the left is from the sagittal T2-weighted sequence (note the bright CSF) and shows a hyperintense lesion in the cervical spinal cord (yellow arrow). Note how the lesion is also causing expansion of the cord. On the right is the corresponding sagittal T1-weighted post-gadolinium image where you can see that the lesion enhances. There are additional metastases in the brainstem (orange arrows).
   Noncompressive Myelopathy

   Noncompressive myelopathy manifests as an intramedullary T2-hyperintense signal without an underlying mass. The differential diagnosis includes vascular, metabolic, inflammatory, infectious, and demyelinating causes.

   Metabolic Causes

   • Subacute Combined Degeneration: Caused by vitamin B12 deficiency, leading to demyelination of the posterior columns. MRI shows symmetric T2 hyperintensity in the posterior columns with an inverted "V" configuration.

   Vascular Causes

   1. Spinal Cord Infarction: Often due to anterior spinal artery ischemia. MRI reveals a linear, pencil-like T2 hyperintensity in the spinal cord, with restricted diffusion on diffusion-weighted imaging.

      

      Fig 28: Sagittal STIR and T2W images shows increased intramedullary signal intensity involving spinal cord from T8-L1 level-S/o infarct

   2. Dural Arteriovenous Fistula (DAVF): Results in venous congestion and chronic cord ischemia. MRI shows spinal cord enlargement with central T2 hyperintensity and serpentine perimedullary flow voids.

      

      Fig 29: Prominent serpinginous extramedullary flow voids are noted in the dural sac circumferrentially predominently in the ventral aspect of the lumbar region.There are subtle areas of T2W hypointensities in the periphery along the surface of the spinal cord.T2W hyperintensities are aloso noted in the cord(edema) along with thinning of cord noted from D1-L2 vertebrae-Dural AV fistula causing compression of cord.

   Inflammatory Causes

   1. Multiple Sclerosis (MS): An autoimmune demyelinating disease. MRI reveals focal T2-hyperintense lesions, often in the cervical spine, with incomplete ring enhancement.

   2. Neuromyelitis Optica Spectrum Disorder (NMO): Characterized by longitudinally extensive transverse myelitis and optic neuritis. MRI shows central T2 hyperintensity involving three or more vertebral segments, often extending into the brainstem.

   3. Acute Disseminated Encephalomyelitis (ADEM): A postinfectious or postvaccination demyelinating disorder. MRI reveals multifocal T2-hyperintense lesions in the spinal cord and brain, often with gray matter involvement.

   Infectious Causes

   • Postviral Acute Transverse Myelitis: Often follows a viral infection. MRI shows segmental T2 hyperintensity with variable enhancement.

   • Neurocysticercosis:
     

     Fig 30: A 60 yrs male patient complaining of back pain since 1 yr MRI LS spine T2 W shows hyperintense lesion at D11-D12 level on post contrast minor enhancement ----Neurocysticercosis
   Idiopathic Acute Transverse Myelitis

   A diagnosis of exclusion, characterized by longitudinally extensive T2 hyperintensity involving two or more vertebral levels. Often reclassified as MS or spinal cord infarction upon further workup.