Addition of Hyperacute MRI Aids in Patient Selection, Decreasing the Use of Endovascular Stroke Therapy

Abstract

A cute ischemic stroke caused by large intracranial arterial occlusion is associated with high morbidity and mortality.1 Arterial recanalization and tissue reperfusion, either by intravenous thrombolysis or endovascular therapy, are the most effective strategy in improving patient outcome. Intravenous tissue-type plasminogen activator (tPA) has proven to be effective in improving clinical outcomes in patients ≤4.5 hours of symptoms onset. 2,3 However, recanalization in the presence of proximal large-vessel occlusion is limited, estimated to be only 5% to 14% for internal carotid artery and 30% to 50% for M1 segment. [4][5][6][7] Endovascular stroke therapy (EST), including the use of mechanical thrombectomy and intra-arterial thrombolytic agents, has emerged as an option for patients who fail to recanalize with or ineligible for intravenous tPA. Although EST has shown effective recanalization rates and a relatively good safety profile, [8][9][10][11][12] most clinical trials have not shown that this strategy improves clinical outcomes. 7,13 This could be explained by either lack of effectiveness or alternatively, by suboptimal patient selection not sufficiently based on the viability of brain tissue.Several neuroimaging techniques, including MRI of the brain, MR perfusion, and computed tomography (CT) perfusion, have been studied to improve patient selection for acute EST by identifying a small core infarct with a large penumbral territory that can be salvaged with reperfusion therapy. [14][15][16] However, these neuroimaging techniques might significantly delay treatment and are not yet proven to improve clinical outcome. 17 Evidence is emerging about possible criteria for selection, such as Yoo et al 15 showing that patients with >70-mL diffusion weighted imaging (DWI) lesion volume in Background and Purpose-The failure of recent trials to show the effectiveness of acute endovascular stroke therapy (EST) may be because of inadequate patient selection. We implemented a protocol to perform pretreatment MRI on patients with large-vessel occlusion eligible for EST to aid in patient selection. In patients considered for EST, we hypothesize that addition of pretreatment MRI to determine the core infarct volume before intervention could improve patient selection. Furthermore, we want to ascertain whether any additional delay to initiation of EST resulted from incorporating the pretreatment MRI into our acute endovascular stroke treatment algorithm. Methods SubjectsUsing our acute stroke endovascular database, between January 2008 and August 2012, we retrospectively identified patients aged ≥18 years who presented to our emergency department or transferred from other hospitals with acute ischemic stroke ≤8 hours since last known well were considered for EST. All patients received acute stroke standard of care treatment, including intravenous tPA if eligible. The institutional review board approved this study.Baseline clinical characteristics and treatment parameters were systematically collected, including demograph...

Susceptibility Vessel Sign on MRI Predicts Favorable Clinical Outcome in Patients with Anterior Circulation Acute Stroke Treated with Mechanical Thrombectomy

“…In the Multicenter Randomized Clinical Trial of Endovascular Treatment for Acute Ischemic Stroke in the Netherlands (MR CLEAN) and the Endovascular Treatment for Small Core and Proximal Occlusion Ischemic Stroke (ESCAPE) trial, 3,4 patients were randomized on the basis of CT. As in other centers, we believe that MR imaging before treatment is, when available, the best imaging technique. [24][25][26] Although we did not specifically measure the length of each MR imaging in our study, our MR imaging protocol is performed without injection and includes 4 short sequences, with an 11-minute acquisition time. This acquisition time is no longer than a CT scan, with and without contrast agent injection.…”

Acute Ischemic Stroke Management Review for the Hospitalist

“…The role of magnetic resonance imaging (MRI) in acute ischemic stroke is a topic of ongoing study. MRI can aid appropriate selection of patients who need endovascular therapy and decrease exposure to invasive procedures in inappropriate patients thus improving outcomes and patient safety (64).…”

Multimodal Diagnostic Imaging for Hyperacute Stroke

“…49 The second study was a single-center cohort analysis in which 2 separate imaging-selection approaches were compared. 50 In the first cohort, patients with proximal artery occlusions were evaluated for intraarterial therapy by using NCCT and CTA, and in a subsequent cohort, DWI was performed in addition to NCCT and CTA. Most important, in both cohorts, the investigators analyzed outcomes in patients who were both treated and excluded from treatment and found that the cohort in which DWI was performed had better 30-day good outcomes (mRS 0 -2: 23.6% versus 9.1%), lower mortality (25% versus 48.5%), and lower symptomatic hemorrhage rates (3.9% versus 10.2%), despite fewer patients being treated endovascularly (51.7% versus 96.6%).…”