Rapid Short MRI Sequence Useful in Eliminating Stroke Mimics Among Acute Stroke Patients Considered for Intravenous Thrombolysis

Abstract

Background Acute stroke teams are challenged by IV-tPA decision making in patients with acute neurological symptoms when the diagnosis is unclear. The purpose of this study was to evaluate the ability of the rapid Brain Attack Team (BAT) MRI in selecting patients for IV-tPA administration who present acutely to the emergency room with stroke-like symptoms and an unclear diagnosis. Methods Consecutive patients were identified who presented within 4.5 hours of onset of stroke-like symptoms and considered for treatment with IV-tPA. When the diagnosis was not clear, a 9-minute BAT MRI was obtained. Stroke risk factors and NIH stroke scale obtained on presentation were compared between patients in whom BAT MRI was obtained and those in whom BAT MRI was not obtained. Similarly, comparisons were made between patients in whom BAT MRI detected abnormalities and those in whom BAT MRI did not detect abnormalities. BAT MRIs were analyzed to determine if radiological findings impacted clinical management and discharge diagnosis. Results In a 30-month period, 432 patients presenting with acute stroke-like symptoms were identified. Of these patients, 82 received BAT MRI. Patients receiving BAT MRI were younger, more likely to be smokers, and less likely to be selected for IV-tPA administration compared to those in whom a more definitive diagnosis of stroke precluded a BAT MRI. Of the 82 BAT MRIs, 25 were read as positive for acute ischemia. The patients with acute ischemia on BAT MRI were older, more likely to be males, have a history of hypercholesterolemia and atrial fibrillation, and more likely to be selected for IV-tPA administration compared to those with a negative BAT MRI. Of the 57 BAT MRIs read as negative for acute ischemia or hemorrhage, discharge diagnoses included TIA, MRI negative stroke, conversion/functional disorder, and multiple other illnesses. Conclusion In patients with acute stroke-like symptoms, BAT MRI may be used to confirm acute ischemic stroke, exclude stroke mimics, and assess candidacy for IV-tPA.

Cost-Effectiveness of Emergent MRI during Stroke Alert to Diagnose Stroke Mimics: Single-Center Experience

“…Various studies have shown the feasibility of using specific MRI sequences as part of acute stroke protocols in patients eligible for IV tPA. 22 We propose that by modifying stroke pathway from algorithm I [CT+CTA≥IV tPA ± neuro-intervention≥ MRI] to algorithm II [Emergent MRI+MRA≥IV tPA ± Neuro-intervention], we can further reduce the cost in stroke pathways by $1,476 to $4,176 per patient by eliminating the cost of CT that was not calculated in our study.…”

Moving From CT to MRI Paradigm in Acute Ischemic Stroke: Feasibility, Effects on Stroke Diagnosis and Long-Term Outcomes

“…The duration of imaging acquisition with MRI can also be reduced by applying a minimal imaging sequence protocol that may omit either perfusion, cerebral time-of-flight, or contrast-based cervical magnetic resonance angiography in early patients with clear IVT or endovascular treatment indications. 22–24…”

“…Despite this nonlinear trend, the median door-to-imaging delay was 27 minutes in both periods, and in the multivariable analysis the imaging paradigm did not have a significant effect (β-coefficient, 8.49 [95% CI, −1.94 to 18.93]; P adj =0.11; Table 2). In the subgroup of potential IVT candidates (patients arriving to the ER within 3.5 hours from known onset and with baseline National Institutes of Health Stroke Scale ≥4), the median delay to imaging was 2 minutes longer in the MRI-paradigm as opposed to CT-paradigm: 21 minutes (IQR, [16][17][18][19][20][21][22][23][24][25][26][27] The proportion of intracranial (±extracranial) arterial imaging with sufficient quality increased during the MRIparadigm (MRI-paradigm, 97.6% versus CT-paradigm, 92.9%; OR unadj , 3.06 [95% CI, 2.08-4.50]; P unadj <0.05) while the proportion of perfusion imaging at baseline with sufficient quality was similar (Table 2).…”

MRI of myositis and other urgent muscle-related disorders

“…However, given the aforementioned limitations in diagnosis, invasive testing, and treatment morbidity, we posit that MRI may have a role yet to play in ACS. We have seen how rapid MRI scans play an important role in acute brain ischemia, using abbreviated protocols to quickly discriminate between strokes to be treated with IV-tPA and stroke mimics [50]. Similarly, the shorter length of time from injury to fasciotomy portends a better outcome for patients with ACS.…”