Scientific Session 05 — Neuroradiology - BrainMonday, May 1, 2017
3143. Emergency Department MRI of Patients With Multiple Sclerosis: Worthwhile or Wasteful?
Pakpoor J*, Saylor D, Izbudak I, Liu L, Yousem D. The Johns Hopkins Medical Institutions, Baltimore, MD
Address correspondence to J. Pakpoor (firstname.lastname@example.org)
Objective: In 2012, an MRI scanner was installed in the emergency department (ED) of our hospital for use 24 hours per day. The following year saw a 51.4% increase in MRI utilization in the ED for neurology consults. Although this shift reduced the burden on the inpatient MRI scanners, the increased utilization of ED MRI raised the question of its added value to patient care for what is still a limited but heavily used hospital resource. We hypothesized that ED MRI use for identifying active demyelination in patients with multiple sclerosis (MS) who present to the ED with neurologic symptoms suspicious for an MS exacerbation would be a low-yield endeavor and have limited impact on management.
Materials and Methods: An automated query of our institution’s radiology information system was used to identify all ED MRI patient encounters in a 2-year period (March 1, 2014–March 1, 2016) in which at least one of the terms “multiple sclerosis,” “MS,” “demyelination,” “demyelinating,” “myelitis,” “optic neuritis,” or “transverse myelitis” appeared anywhere in the ED MRI report. We evaluated patients with an established MS diagnosis at the time of ED presentation and for whom an MS exacerbation was part of the differential diagnosis according to the patients’ electronic medical records. Details surrounding patient disposition, diagnosis, and management were determined.
Results: Of 115 patients in our study, 48 (41.7%) were ultimately diagnosed with an MS exacerbation. Nearly all patients with MS exacerbations (87.5%, 42/48) had active demyelination on their ED MR images, identified on 30.6% (33/108) of brain MR images and 20.4% (19/93) of spinal MR images. The presence of active demyelination was significantly associated with the ultimate diagnosis of an MS exacerbation (p < 0.001). Activity isolated to the spinal cord on MRI (i.e., not found on concurrent brain MRI) was present in only 9 of 93 (9.7%) cases. Pseudoexacerbations accounted for 18 of the alternative diagnoses. Furthermore, we found that for 39% of patients (45/115), the electronic medical records explicitly indicated that a management decision to admit the patient, administer IV steroids, or both for an MS exacerbation was determined by findings of activity on MRI.
Conclusion: ED MRI is a worthwhile endeavor from a diagnostic standpoint for MS exacerbations despite not being part of the diagnostic criteria. This finding has corresponding downstream impact on management decisions to admit a patient, administer IV steroids, or both. However, we found that immediate concurrent spinal MRI utilization is a questionable addition to brain MRI because of its particularly low yield in identifying isolated spinal active demyelination, especially in the thoracic spine. Additionally, we raise the possibility that physicians may be placing undue weight on MRI findings in diagnosing MS exacerbations relative to history and physical examination findings. An examination of this possibility and a full cost-benefit analysis of ED MRI for suspected MS exacerbations represent important avenues for future work.