Barow E, et al. - Via a secondary post hoc analysis of the randomized clinical WAKE-UP trial of magnetic resonance imaging–guided intravenous alteplase administrated to 503 lacunar infarcts patients with stroke of unknown onset, the researchers sought to study the efficacy and safety of intravenous thrombolysis. Since, the WAKE-UP trial was not powered to demonstrate the efficacy of treatment in subgroups of patients, in comparison with those experiencing other stroke subtypes, the association among intravenous alteplase with functional outcome did not differ in patients with imaging-defined lacunar infarcts.