Background and Purpose-For a biomarker to serve as an auxiliary or surrogate outcome measure, it must be tightly correlated with and causally related to functional clinical outcome. Vessel recanalization is a potential surrogate outcome marker for functional outcome in trials of thrombolytic and mechanical recanalization therapies in acute stroke, but the correlation of recanalization and clinical outcome has not been previously systematically reviewed. Methods-Through Medline search, we identified and abstracted recanalization and outcome data from all articles published between 1985 and 2002 that assessed vessel recanalization, either spontaneous or therapeutically induced, in acute ischemic stroke. Results-Fifty-three studies encompassing 2066 patients reported recanalization rates. Recanalization rates categorized according to intervention were: spontaneous (24.1%), intravenous fibrinolytic (46.2%), intra-arterial fibrinolytic (63.2%), combined intravenous-intra-arterial (67.5%), and mechanical (83.6%). Clinical outcome data categorized by success or failure in achieving recanalization was available from 33 articles encompassing 998 patients. Good functional outcomes at 3 months were more frequent in recanalized versus nonrecanalized patients with odds ratio of 4.43 (95% CI, 3.32 to 5.91). Three-month mortality was reduced in recanalized patients (odds ratio, 0.24; 95% CI, 0.16 to 0.35).Rates of symptomatic hemorrhagic transformation did not differ between the 2 groups (odds ratio, 1.11; 95% CI, 0.71 to 1.74). Conclusions-Formal meta-analysis confirms a strong correlation between recanalization and outcome in acute ischemic stroke. Recanalization is strongly associated with improved functional outcomes and reduced mortality. These findings suggest that recanalization is an appropriate biomarker of therapeutic activity in early phase trials of thrombolytic treatment in acute ischemic stroke. (Stroke. 2007;38:967-973.)

Campbell, B. C.V. et al. (2019) Penumbral imaging and functional outcome in patients with anterior circulation ischaemic stroke treated with endovascular thrombectomy versus medical therapy: a meta-analysis of individual patient-level data.ABSTRACT Background: CT-perfusion (CTP) and MRI may assist patient selection for endovascular thrombectomy. We aimed to establish whether imaging assessments of ischaemic core and penumbra volumes were associated with functional outcomes and treatment effect.

Background and Purpose-An optimal strategy for management of symptomatic intracranial atherosclerotic stenosis (ICAS) has not yet been established. We compared the efficacy of 2 combinations of antiplatelets, aspirin plus cilostazol (cilostazol group) verus aspirin plus clopidogrel (clopidogrel group), on the progression of ICAS, which is known to be associated with clinical stroke recurrence. Methods-In this investigator-initiated double-blind trial, 457 patients with acute symptomatic stenosis in the M1 segment of the middle cerebral artery or the basilar artery were randomly allocated into either a cilostazol group or a clopidogrel group. After 7 months of treatment, follow-up MR angiogram and MRI were performed. The primary end point was the progression of ICAS in comparison with stenosis on the baseline MR angiogram. Secondary end points included the occurrence of new ischemic lesions on MRI, composite of cardiovascular events, and major bleeding complications. Results-Cardiovascular events occurred in 15 of 232 patients (6.4%) in the cilostazol group and 10 of 225 (4.4%) in the clopidogrel group (Pϭ0.312). Cilostazol did not reduce the progression of symptomatic ICAS (20 of 202) compared to clopidogrel (32 of 207) (odds ratio, 0.61; Pϭ0.092), although favorable changes in serum lipoproteins were observed in the cilostazol group. There were no significant differences between the 2 groups with respect to new ischemic lesions (18.7% versus 12.0%; Pϭ0.078) and major hemorrhagic complications (0.9% versus 2.6%; Pϭ0.163). Conclusions-This trial failed to show significant difference in preventing progression of ICAS and new ischemic lesions between the 2 combination antiplatelet therapies in the patients with symptomatic ICAS. Clinical Trial Registration-URL: http://www.clinicaltrials.gov. Unique identifier: NCT00130039.