Complete Spine MRI for Suspected Multiple Sclerosis
Yes, perform whole spinal cord MRI imaging of the entire cord (cervical through thoracolumbar) in patients with new onset symptoms suggestive of MS, particularly when presenting with spinal cord symptoms or when brain MRI is equivocal or inconclusive. 1
When Complete Spine MRI is Mandatory
Spinal cord MRI must always be performed in the following scenarios: 1
Patients presenting with spinal cord symptoms at disease onset - This is mandatory to exclude non-demyelinating pathology such as compression, spinal cord tumor, neuromyelitis optica, or vasculitides 1
When brain MRI results are equivocal or inconclusive - For example, during differential diagnosis of cerebrovascular disorders, autoimmune inflammatory disorders, or age-related white matter changes 1
When brain MRI shows lesions typical of MS but insufficient to fulfill diagnostic criteria for dissemination in space (DIS) 1
Why Image the Entire Cord
Imaging of the entire spinal cord (not just cervical) is critical because approximately 40% of spinal cord lesions are located in the thoracolumbar region. 1 Missing these lesions by limiting imaging to cervical segments alone would significantly reduce diagnostic sensitivity. 1
Asymptomatic cord lesions are found in 30-40% of patients with clinically isolated syndrome, and whole cord imaging demonstrates that the presence of even one spinal cord lesion identifies patients at higher risk of MS confirmation. 1
Technical Protocol for Complete Spine Imaging
The standardized protocol requires: 1, 2
Minimum field strength of 1.5 T (unlike brain imaging, 3.0 T confers no additional diagnostic value for spinal cord) 1, 2
At least two sets of sagittal images with different contrasts - Mandatory sequences include T2-weighted and proton-density and/or STIR (short-tau inversion recovery) 1, 2
Slice thickness of 3 mm to increase confidence in lesion detection 1, 2
Axial imaging through suspicious lesions using 2D or 3D T2-weighted spin-echo sequences, particularly if sagittal images are suboptimal 1
Contrast-enhanced T1-weighted sequences only if T2 lesions are present (unlike brain imaging where contrast is always given initially) 1, 2
Timing and Workflow Considerations
Perform spinal cord MRI directly after contrast-enhanced brain MRI in a "one-stop shop" strategy. 1 This approach saves time and decreases the need for additional contrast administration, as spinal cord lesions that show contrast enhancement are commonly associated with new clinical symptoms. 1
Diagnostic Value and Limitations
For dissemination in space (DIS): Whole spinal cord MRI is highly recommended and valuable, as the spinal cord rarely exhibits incidental MS-like abnormalities even in older patients (unlike the brain). 1
For dissemination in time (DIT): Spinal cord imaging has limited value in patients without accrual of deficits referable to the spine, since new clinically silent cord lesions are not frequent. 1
Critical Pitfalls to Avoid
Do not limit imaging to cervical spine only - This misses 40% of lesions in the thoracolumbar region and significantly reduces diagnostic yield. 1
Do not skip spinal cord imaging when brain MRI is "almost diagnostic" - In patients with non-spinal clinically isolated syndrome not fulfilling brain MRI criteria for DIS, spinal cord lesions can provide the additional evidence needed for diagnosis. 1
Be aware of technical challenges - The spinal cord is thin and mobile, prone to ghosting artifacts from breathing and CSF pulsation, and truncation artifacts that can lead to false-positive or false-negative interpretations. 1 Using spatial presaturation slabs and fast imaging sequences with spinal phase-array coils minimizes these issues. 1