Clinical suspicion of inflammatory or demyelinating process (e.g., clinically isolated syndrome, multiple sclerosis, other demyelinating disease), as indicated by 1 or more of the following:
Findings of suspected transverse myelitis (idiopathic or in conjunction with multiple sclerosis) in thoracic spinal cord
Suspected multiple sclerosis and 1 or more of the following:
Signs or symptoms of myelopathy
Ascending numbness or tingling (e.g., from foot to trunk)
Rheumatic diseases with demyelination mimicking multiple sclerosis (e.g., Sjogren syndrome, systemic lupus erythematosus, and antiphospholipid syndrome) have not been ruled out.
Findings of suspected tethered cord, as indicated by 1 or more of the following:
Cutaneous manifestations of occult spina bifida (e.g., nevus, lipomas, tufts of hair, hemangiomas, dimple overlying spine)
Urinary dribbling or lack of bladder control
Abnormal urodynamic tests
Gait abnormality or difficulty
Spinal curvature or scoliosis, as indicated by 1 or more of the following:
Other suspected congenital spinal conditions, as indicated by 1 or more of the following:
Myelomeningocele
Myelocele
Diastematomyelia (i.e., split cord malformation)
Dorsal dermal sinus
Intradural lipoma
Hydromyelia
Split notochord syndrome
Discussion
Thoracic spine MRI is indicated for evidence of thoracic spinal cord compression, trauma, neoplasm or infection.
For suspicion of metastatic disease to the spine in patients with known primary malignancy, whole-spine MRI is considered first-line imaging because multiple sites of spinal cord compression are seen in up to 1/3 of patients with metastatic epidural spinal cord compression. MRI is useful for staging neoplastic meningitis for palliative radiotherapy.
Thoracic MRI is a first-line option for suspected thoracic spinal infection and inflammation, including spondylitis, epidural abscess, osteomyelitis, and spinal tuberculosis.
For clinical suspicion of a demyelinating disease such as multiple sclerosis in patients presenting with a clinically isolated syndrome, most commonly manifested as unilateral optic neuritis, brainstem syndrome, or partial myelitis, diagnostic criteria have been developed based on the demonstration of CNS lesions disseminated in space and disseminated in time on MRI imaging of the brain and, if appropriate, on spinal cord imaging. Spinal cord involvement is common with multiple sclerosis, and lesions may be present solely in the spinal cord in up to 25% of patients, with lesions in the cervical spine occurring more commonly than in the thoracic spine. An expert consensus panel recommends spinal cord imaging for patients with suspected demyelinating disease who present with signs or symptoms of spinal cord involvement or if the number of lesions on brain MRi is insufficient to meet established criteria for multiple sclerosis.
For scoliosis, a review concluded that MRI is not routinely indicated for pain in the absence of abnormal neurologic examination findings or an atypical curve, such as a left-sided curve (levoscoliosis), a short segment or kyphosis near the curve apex. In a prospective study of 250 scoliosis patients undergoing surgery, factors predicting neural axis deformity associated with scoliosis included age at first visit less than 11 years, left-sided thoracic curvature, thoracic kyphosis greater than 30 degrees, neurologic deficit (highest association with sustained clonus or asymmetric loss of superficial abdominal reflex), and presence of moderate or severe back pain.
Reference
Milliman Care Guidelines, “Ambulatory Care”, 15th Edition.