Specialist Perspectives on the Imaging Selection of Large Vessel Occlusion in the Late Window

Abstract

Background The proper imaging modality for use in the selection of patients for endovascular thrombectomy (EVT) presenting in the late window remains controversial, despite current guidelines advocating the use of advanced imaging in this population. We sought to understand if clinicians with different specialty training differ in their approach to patient selection for EVT in the late time window. Methods We conducted an international survey of stroke and neurointerventional clinicians between January and May 2022 with questions focusing on imaging and treatment decisions of large vessel occlusion (LVO) patients presenting in the late window. Interventional neurologists, interventional neuroradiologists, and endovascular neurosurgeons were defined as interventionists whereas all other specialties were defined as non-interventionists. The non-interventionist group was defined by all other specialties of the respondents: stroke neurologist, neuroradiologist, emergency medicine physician, trainee (fellows and residents) and others. Results Of 3000 invited to participate, 1506 (1027 non-interventionists, 478 interventionists, 1 declined to specify) physicians completed the study. Interventionist respondents were more likely to proceed directly to EVT (39.5% vs. 19.5%; p < 0.0001) compared to non-interventionist respondents in patients with favorable ASPECTS (Alberta Stroke Program Early CT Score). Despite no difference in access to advanced imaging, interventionists were more likely to prefer CT/CTA alone (34.8% vs. 21.0%) and less likely to prefer CT/CTA/CTP (39.1% vs. 52.4%) for patient selection ( p < 0.0001). When faced with uncertainty, non-interventionists were more likely to follow clinical guidelines (45.1% vs. 30.2%) while interventionists were more likely to follow their assessment of evidence (38.7% vs. 27.0%) ( p < 0.0001). Conclusion Interventionists were less likely to use advanced imaging techniques in selecting LVO patients presenting in the late window and more likely to base their decisions on their assessment of evidence rather than published guidelines. These results reflect gaps between interventionists and non-interventionists reliance on clinical guidelines, the limits of available evidence, and clinician belief in the utility of advanced imaging. Supplementary Information The online version of this article (10.1007/s00062-023-01284-0) contains supplementary material, which is available to authorized users.

CLEAR Thrombectomy Score: An Index to Estimate the Probability of Good Functional Outcome With or Without Endovascular Treatment in the Late Window for Anterior Circulation Occlusion

“…Many of these imaging features are not widely used or require expensive software that may not be available at many institutions. 41 , 42 , 43 We have also previously shown that clinical outcomes are no different for patients selected for EVT based on perfusion imaging, magnetic resonance imaging, or computed tomography in routine clinical practice. 29 , 44 That said, fewer than half of the patients in this cohort underwent perfusion imaging, so these metrics were not included in the model.…”

Endovascular Therapy for Acute Stroke: New Evidence and Indications

“…56) However, maximizing the number of patients who can be helped necessitates that we broaden our criteria for interventions and update our guidelines. 56,82) Given the low NNT of EVT in stroke, broadening our criteria may dilute the overall effect of EVT but reach a greater number of patients overall that will benefit. We must also search for optimizing firstpass effect [83][84][85] and adjunctive therapies to help maximize the benefit of EVT.…”

Endovascular Thrombectomy for Anterior Circulation Large Vessel Occlusion Stroke: An Evolution of Trials

“…39 Moreover, specialist perspectives may differ on choice of neuroimaging study in the late window. 40 The Society of Vascular and Interventional Neurology Guidelines state that NCCT can be used to evaluate patients presenting in the late window for EVT treatment as an alternative to CTP or MRI, particularly when access to CTP or MRI is limited. 41 The MR CLEAN LATE randomized trial compared EVTversus medical management for patients presenting between 6 and 24 hours of time last seen well based on NCCT and CTA collateral selection.…”