While it’s not a part of established diagnostic criteria, the use of MRI in the emergency department (ED) to evaluate multiple sclerosis (MS) patients for possible exacerbations pays good diagnostic and care-management dividends, according to study conducted at Johns Hopkins and published online Oct. 6 in the American Journal of Neuroradiology.
Senior study author David Yousem, MD, MBA, and colleagues looked into the “worthwhile vs. wasteful” question after noting increasing use of their ED’s MRI scanner and wondering if the pricey exams added demonstrable value to certain patient groups.
For the present study, they specifically hypothesized that the use of emergency MRI to identify active demyelination in MS patients presenting with new neurologic symptoms would yield little useful diagnostic information.
To test this, the team reviewed the medical records of 115 patients with MS who received emergency department MRI scans for a suspected MS exacerbation over the two-year period ending in March of this year.
They found that 41.7 percent (48 of the 115) were ultimately diagnosed with an MS exacerbation.
Of these 48, nearly all (87.5 percent, n = 42) had active demyelination on their emergency department MR imaging. The demyelination was identified on 30.6 percent (33/108) of brain MRIs and 20.4 percent (19/93) of spinal MRIs.
The presence of active demyelination at MRI was thus significantly associated with the ultimate diagnosis of an MS exacerbation (P < .001), the authors report.
In their conclusions, Yousem and colleagues note that the demonstration of MRI’s clear utility for MS patients in these clinical situations “has corresponding downstream impact on management decisions to admit and/or administer intravenous steroids.”
However, they raise the question of whether clinicians “over-rely on emergency department imaging for making exacerbation diagnoses.”
“Additionally, spinal MR imaging is of questionable value as an addition to brain MR imaging due to a low yield of isolated spinal disease.”
Prompting this conclusion was the team’s finding that MR imaging activity isolated to the spinal cord—that which didn’t turn up on concurrent brain MR imaging—was present in only 9 of 93 (9.7 percent) cases.