Intracranial atherosclerotic stenosis (ICAS) is one of the most common causes of stroke worldwide, accounting for 8% to 10% of strokes in North America and 30% to 50% of strokes in Asia.
1-5 The current recommended strategy for stroke prevention in patients with ICAS is standard medical therapy.
6 In recent years, standard medical therapy has substantially reduced stroke recurrence in patients with ICAS.
4,7,8 However, a subset of patients are at a high risk for stroke recurrence despite medical treatment.
9,10 For instance, patients with border zone infarcts and impaired collaterals in the Stenting and Aggressive Medical Management for Preventing Recurrent Stroke in Intracranial Stenosis (SAMMPRIS) trial had a 37% 1-year stroke recurrence rate.
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