MRI is the investigation of choice for the following conditions:

• lesions in the spinal cord
• spinal cord inflammation/demyelination
• spinal trauma
• spinal cord infarcts
• discitis and osteomyelitis
• epidural abscess
• developmental abnormalities of the spine
• spinal cord compression
• post-operative scarring and arachnoiditis
• disc herniation
• syringomyelia
• tumours of the spine and spinal cord
  

It may also be indicated where CT scan is impracticable.

• When compared to other imaging methods, MRI has proven value when correlated with surgical findings, being most effective in demonstrating degenerative spinal diseases, vertebral inflammatory lesions, congenital malformations, traumatic damage and in the evaluation of patients with signs and symptoms of spinal cord compression.

Alert: http://www.fda.gov/cdrh/safety/neurostim.html