LAUSR

In their retrospective analysis of 184 patients treated with intravenous thrombolysis for an unknown time of stroke onset, Macha et al. compared treatment times and outcomes based on assessment using multimodal computed tomography (CT) or magnetic resonance imaging (MRI). Unsurprisingly, patients selected for thrombolysis based on CT were treated more quickly than those who underwent brain MRI (mean difference 28 minutes); however, there were no significant differences in the rate of symptomatic intracranial hemorrhage or favorable outcome at 90 days between the imaging groups. Kumar and Singh comment that MRI has other advantages, such as the detection of microhemorrhages, higher spatial resolution for brain injury, lack of intravenous contrast requirement, and more rapid imaging acquisition with recent technological advancements. The investigators agree that MRI offers unique advantages over CT; however, these advantages are outweighed by the more expedient delivery of acute stroke care with CT, as has been confirmed in the recent EXTEND trial. Both the investigators and the commenters share optimism about the use of tenecteplase over alteplase as a means of shortening treatment delays; however, the safety and efficacy of tenecteplase beyond 4.5 hours (or in the unknown time window) have not yet been established.