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Imaging of the Spine in Multiple Sclerosis

Practice Essentials

Magnetic resonance imaging (MRI) was first used to visualize multiple sclerosis (MS) in the upper cervical spine in the late 1980s.
Spinal MS is often associated with concomitant brain lesions; however, as many as 20% of patients with spinal lesions do not have intracranial plaques. Contrary to the white and gray matter in the brain, white and gray matter can both be affected in the spine. No strong correlation has been established between the extent of the plaques and the degree of clinical disability.
 Spinal cord atrophy is most relevant to progressive forms of MS (primary progressive and secondary progressive), in which it closely links to physical disability.

MRI is currently considered to be the most sensitive diagnostic imaging modality for revealing demyelinating plaques, as recommended by the Consortium of Multiple Sclerosis Centers.
No specific field strength is recommended. Gadolinium is typically favored. MRI shows abnormalities in 95% of patients with clinically definitive MS.

On long TR sequences, MRI scans show areas of demyelination as high-signal areas. Lesions of other etiologies (eg, viral myelitis, acute disseminated encephalomyelitis [ADEM]) may resemble MS plaques and must be considered along with the clinical history and the patient’s presenting signs and symptoms. (For patient education information, see Multiple Sclerosis.)

According to an international group of neurologists and radiologists, the spinal cord MR imaging protocol for MS should include sagittal T1-weighted and proton attenuation, STIR or phase-sensitive inversion recovery, axial T2- or T2-weighted imaging through suspicious lesions, and, in some cases, postcontrast gadolinium-enhanced T1-weighted imaging.

(See the image below).

Sagittal, T2-weighted magnetic resonance image of

Sagittal, T2-weighted magnetic resonance image of the cervical spinal cord in a woman aged 27 years showing a fusiform area of increased signal intensity representing a multiple sclerosis plaque.

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Careful review of the patient’s medical history and an evaluation of the brain with MRI can prove helpful in the diagnosis, especially in young females. MS is considered to be the most common demyelinating process involving the central nervous system (CNS).

Imaging plays an important role in MS, as noted in the McDonald Criteria (see Table 1). It is important to note that the McDonald Criteria were largely collected from adult white European and North American populations. MRI is used to demonstrate lesion dissemination in time (DIT) and space (DIS).

 

Table 1. McDonald Criteria, Revised 2017 (Open Table in a new window)

  Number of lesions with       objective clinical evidence Additional data needed for a diagnosis of MS
≥2 clinical attacks ≥2 none
≥2 clinical attacks

≥1 (as well as clear-cut historical evidence of 

a previous attack involving a lesion in a distinct anatomic location)

none
≥2 clinical attacks 1 Dissemination in space demonstrated by an additional clinical attack implicating a different CNS site or by MRI
1 clinical attack ≥2 Dissemination in time demonstrated by an additional clinical attack or by MRI OR demonstration of CSF-specific oligoclonal bands
1 clinical attack 1 Dissemination in space demonstrated by an additional clinical attack implicating a different CNS site or by MRI AND dissemination in time demonstrated by an additional clinical attack or by MRI OR demonstration of CSF-specific oligoclonal bands.

 

If the 2017 McDonald Criteria are fulfilled and there is no better explanation for the clinical presentation, the diagnosis is multiple sclerosis. If multiple sclerosis is suspected by virtue of a clinically isolated syndrome but the 2017 McDonald Criteria are not completely met, the diagnosis is possible multiple sclerosis. If another diagnosis arises during the evaluation that better explains the clinical presentation, the diagnosis is not multiple sclerosis. 

Other key changes to the McDonald Criteria include the following:

Brain stem and cord lesions can now be counted among the 2 lesions disseminated in space and time.

CSF oligoclonal bands can now be used to substitute for demonstration of dissemination in time in some settings.

Both asymptomatic and now symptomatic MRI lesions can be considered in determining dissemination in space (optic nerve lesions are still excluded).

Cortical lesions have been added to juxtacortical lesions as determinant for dissemination in space.

 

Radiologically isolated syndrome 

Radiologically isolated syndrome (RIS) describes cases in which McDonald imaging criteria meet DIT and DIS but lack corresponding clinical symptoms. The exact significance is still a subject of debate. Some authors suggested that this could represent a stage preceding clinical isolated syndrome (CIS). In an extensive review of the RIS literature, Granberg et al
emphasized that approximately two thirds of cases show radiologic progression and one third develop clinical symptoms at 5-year follow-up. They also point out that clinical conversion is more likely when cervical cord lesions are present. However, further studies are needed to determine patient stratification and define the role of disease-modifying drugs in RIS.

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