Magnetic resonance imaging (MRI) plays a critical role in clinical management of multiple sclerosis (MS). It is key in establishing early diagnosis, even before the first clinical event, it enables assessment of disease severity and prognosis, and it assists in determining whether a given disease modifying therapy (DMT) is effective.1
A recent article1 reviews appropriate use of MRI in the diagnosis and treatment of MS. The authors note that, while history and neurologic exam remain key, MRI “often proves more sensitive a clinical indicator of disease activity.” MRI can detect lesions that fall outside the optic nerve, spinal cord, brainstem, or primary motor/sensory regions. Since these lesions may be asymptomatic, damage to brain tissue may have occurred before the patient presents for an examination. Early MRI can detect these lesions and early intervention can be initiated.
Recommended MRI Sequences and Regions
The authors discuss sequences and regions in MRI brain imaging (Table 1). They recommend the administration of gadolinium before T2-weighted and fluid-attenuated inversion recovery (FLAIR) sequences to “permit longer circulation time and greater lesion conspicuity.” After gadolinium scans, T1-weighted spin echo sequence should be acquired in at least two planes of view to “positively confirm indeterminate lesions.”
The use of spinal cord imaging is controversial. It may play an important role in diagnosis, but may be less sensitive in detecting subclinical disease activity. Moreover, in contrast to brain imaging, it is difficult to quantify lesions in spinal cord imaging. The authors recommend individualizing spinal cord imaging on an as-needed basis.