CT- versus MRI-Based Imaging for Thrombolysis and Mechanical Thrombectomy in Ischemic Stroke: Analysis from the Austrian Stroke Registry

Abstract

Background and Purpose It is unclear whether a particular stroke imaging modality offers an advantage for the acute stroke treatment. The aim of this study was to compare procedure times, efficacy and safety of thrombolysis and/or thrombectomy based on computed tomography (CT) versus magnetic resonance imaging (MRI) acute stroke imaging.Methods Data of stroke patients who received intravenous thrombolysis (IVT) and/or mechanical thrombectomy (MT) were extracted from a nationwide, prospective stroke unit registry and categorized according to initial imaging modality. Study endpoints included procedure times, symptomatic intracerebral hemorrhage (sICH), early neurological improvement, 3-month functional outcome by modified Rankin Scale (mRS) and mortality.Results Stroke patients (n=16,799) treated with IVT and 2,248 treated with MT were included. MRI-guided patients (n=2,599) were younger, had less comorbidities and higher rates of strokes with unknown onset as compared to CT-guided patients. In patients treated with IVT, no differences were observed regarding the rates of functional outcome by mRS 0–1 (adjusted odds ratio [OR], 0.87; 95% confidence interval [CI], 0.71 to 1.05), sICH (adjusted OR, 0.82; 95% CI, 0.61 to 1.08), and mortality (adjusted OR, 0.88; 95% CI, 0.63 to 1.22). Patients undergoing MT selected by MRI as compared to CT showed equal rates of functional outcome by mRS 0–2 (adjusted OR, 0.87; 95% CI, 0.65 to 1.16), sICH (adjusted OR, 0.9; 95% CI, 0.51 to 1.69), and mortality (adjusted OR, 0.62; 95% CI, 0.35 to 1.09). MRI-guided patients showed a significant intrahospital delay of about 20 minutes in both the IVT and the MT group.Conclusions This large non-randomized comparison study indicates that CT- and MRI-guided patient selection for IVT/MT may perform equally well in terms of functional outcome and safety.

Acute infarct segmentation on diffusion-weighted image using deep learning algorithm and RAPID DWI: a comprehensive stroke center clinical validation study

“…In clinical trials and the real world, computed tomography (CT) perfusion or angiography is the mainstay due to its faster scan time. 4, 5, 22, 23 It has been hypothesized that CT-based decision making improves clinical outcome compared to MRI-based decision making since the time between stroke onset and reperfusion is the most crucial factor in determining stroke patients ‘ outcomes. 24 Nonetheless, accumulating evidence from real-world data has demonstrated that decisions based on MRI are not inferior to those based on CT, 22, 23, 25 despite not having been demonstrated in randomized clinical trials.…”

“…4, 5, 22, 23 It has been hypothesized that CT-based decision making improves clinical outcome compared to MRI-based decision making since the time between stroke onset and reperfusion is the most crucial factor in determining stroke patients ‘ outcomes. 24 Nonetheless, accumulating evidence from real-world data has demonstrated that decisions based on MRI are not inferior to those based on CT, 22, 23, 25 despite not having been demonstrated in randomized clinical trials. In addition, precise infarct segmentation without inter- or intra-rater variability enables investigations on serial DWIs, infarct progression prediction, and infarct–functional anatomy connection.…”

Pitfalls in the diagnosis of post‐TAVI (transcatheter aortic valve implantation) stroke

“…6 Although the routine use of cerebral embolic protection devices remains controversial, 7 its use may be warranted for patients with marked valvular calcification. While the choice of imaging modality for MT (i.e., CT vs. MRI) may not influence the patient outcomes in ordinary ischemic stroke patients 8 and the modality with the greater impact on the selection of major treatment strategies better be chosen in principle, CT/CTA may be given priority in the initial evaluation of patients suspected of post-TAVI stroke, considering poor detectability of calcification on MRI.…”

“…Although the routine use of cerebral embolic protection devices remains controversial, 7 its use may be warranted for patients with marked valvular calcification. While the choice of imaging modality for MT (i.e., CT vs. MRI) may not influence the patient outcomes in ordinary ischemic stroke patients 8 and the modality with the greater impact on the selection of major treatment strategies better be chosen in principle, CT/CTA may be given priority in the initial evaluation of patients suspected of post‐TAVI stroke, considering poor detectability of calcification on MRI. Mechanical thrombectomy, particularly the combined technique, remains the mainstay of treatment for calcified cerebral embolus, 9 and surgical embolectomy may be considered as a rescue measure for those with a large calcified embolus refractory to MT, 10 as seen in this case.…”

Current and future trends in acute ischemic stroke treatment: direct-to-angiography suite, middle vessel occlusion, large core, and minor strokes

“…Despite the subjective perception of timely vessel imaging evaluation by either magnetic resonance imaging (MRI) or especially CTA, current data show that patients in whom CTA is performed before transfer to the EVT center from a primary stroke center have a time delay of at least 62 min [15] This aligns with a 24 min delay reported by a high-volume, efficient, comprehensive stroke center in Barcelona, Spain [16] . Furthermore, expected treatment delays with MR-based imaging are approximately 20 min more than for CT-based protocols [17] .…”