Background and Purpose: Mechanical thrombectomy (MT) is the recommended treatment for acute ischemic stroke caused by anterior circulation large vessel occlusion. However, despite a high rate of reperfusion, the clinical response to successful MT remains highly variable in the early time window where optimal imaging selection criteria have not been established. We hypothesize that the baseline perfusion imaging profile may help forecast the clinical response to MT in this setting. Methods: We conducted a prospective multicenter cohort study of patients with large vessel occlusion–related acute ischemic stroke treated by MT within 6 hours. Treatment decisions and the modified Rankin Scale evaluation at 3 months were performed blinded to the results of baseline perfusion imaging. Study groups were defined a posteriori based on predefined imaging profiles: target mismatch (TMM; core volume <70 mL/mismatch ratio >1.2 and mismatch volume >10 mL) versus no TMM or mismatch (MM; mismatch ratio >1.2 and volume >10 mL) versus no MM. Functional recovery (modified Rankin Scale, 0–2) at 3 months was compared based on imaging profile at baseline and whether reperfusion (modified Thrombolysis in Cerebral Infarction 2bc3) was achieved. Results: Two hundred eighteen patients (mean age, 71±15 years; median National Institutes of Health Stroke Scale score, 17 [interquartile range, 12–21]) were enrolled. Perfusion imaging profiles were 71% TMM and 82% MM. The rate of functional recovery was 54% overall. Both TMM and MM profiles were independently associated with a higher rate on functional recovery at 3 months Adjusted odds ratios were 3.3 (95% CI, 1.4–7.9) for TMM and 5.9 (95% CI, 1.8–19.6) for MM. Reperfusion (modified Thrombolysis in Cerebral Infarction 2bc3) was achieved in 86% and was more frequent in TMM and MM patients. Reperfusion was associated with a higher rate of functional recovery in MM and TMM patients but not among those with no MM. Conclusions: In this cohort study, about 80% of the patients with a large vessel occlusion–related acute ischemic stroke had evidence of penumbra, regardless of infarction volume. Perfusion imaging profiles predict the clinical response to MT.
Acute ischaemic stroke represents the most common cause of new sudden neurological deficit, but other diseases mimicking stroke happen in about one-third of the cases. Magnetic resonance imaging (MRI) is the best technique to identify those ‘stroke mimics’. In this article, we propose a diagnostic approach of those stroke mimics on MRI according to an algorithm based on diffusion-weighted imaging (DWI), which can be abnormal or normal, followed by the results of other common additional MRI sequences, such as T2 with gradient recalled echo weighted imaging (T2-GRE) and fluid-attenuated inversion recovery (FLAIR). Analysis of the signal intensity of the parenchyma, the intracranial arteries and, overall, of the veins, is crucial on T2-GRE, while anatomic distribution of the parenchymal lesions is essential on FLAIR. Among stroke mimics with abnormal DWI, T2-GRE demonstrates obvious abnormalities in case of intracerebral haemorrhage or cerebral amyloid angiopathy, but this sequence also allows to propose alternative diagnoses when DWI is negative, such as in migraine aura or headaches with associated neurological deficits and lymphocytosis (HaNDL), in which cortical venous prominence is observed at the acute phase on T2-GRE. FLAIR is also of major interest when DWI is positive by better showing evocative distribution of cerebral lesions in case of seizure (involving the hippocampus, pulvinar and cortex), hypoglycaemia (bilateral lesions in the posterior limb of the internal capsules, corona radiata, striata or splenium of the corpus callosum) or in posterior reversible encephalopathy syndrome (PRES). Other real stroke mimics such as mitochondrial myopathy, encephalopathy, lactic acidosis, stroke-like episodes (MELAS), Susac’s syndrome, brain tumour, demyelinating diseases and herpes simplex encephalitis are also included in our detailed and practical algorithm. • About 30% of sudden neurological deficits are due to non-ischaemic causes. • MRI is the best technique to identify stroke mimics. • Our practical illustrated algorithm based on DWI helps to recognise stroke mimics.
Patients treated with acute carotid stenting (CAS) may have higher odds of a favorable outcome than those treated without CAS during thrombectomy in tandem occlusions. Antiplatelet therapy is associated with CAS to avoid stent thrombosis, which occurs in around 20% of patients and negatively impacts outcomes. In this study we compared two antiplatelet strategies in tandem occlusion strokes treated with CAS and intracranial thrombectomy in clinical practice.The Endovascular Treatment in Ischemic Stroke Registry is an ongoing prospective observational study involving 21 comprehensive stroke centers performing thrombectomy in France. We analyzed patients with atherosclerotic tandem occlusions treated with acute CAS and intracranial thrombectomy who received at least one antiplatelet agent. Aggressive antiplatelet therapy included oral or intravenous glycoprotein (GP) IIb/IIIa or P2Y12 inhibitors. The primary outcome was cervical carotid artery patency at day 1 imaging follow-up.Among the 187 included patients, 124 (66.3%) received aspirin alone and 63 (33.7%) received aggressive antiplatelet therapy. There was no significant difference regarding safety outcomes, especially in symptomatic intracerebral hemorrhage, parenchymal hematoma, and procedural complications. There was a significantly higher rate of carotid stent patency at day 1 in the aggressive antiplatelet therapy group (81.7% vs 97.1%, aOR 17.49, 95% CI 1.10 to 277.2, p=0.042). Odds of favorable functional outcome (90-day modified Rankin Scale score 0-2) were similar between the groups (OR 3.04, 95% CI 0.64 to 14.25, p=0.158).In tandem occlusions treated with CAS plus thrombectomy, an aggressive antiplatelet regimen was associated with an increased rate of carotid stent patency at day 1 without safety concerns. Randomized trials are warranted to confirm these findings.
