Can Perfusion Imaging Extend Time Window for IV Thrombolysis?

Perfusion imaging has allowed clinicians to select stroke patients with salvageable brain tissue for mechanical thrombectomy up to 24 hours after symptom onset, but whether a similar approach can identify patients who would benefit from intravenous thrombolysis beyond the current 4.5-hour time window or with stroke symptoms upon awakening is less clear.

Investigators conducted a systematic review and individual patient-level meta-analysis comparing intravenous thrombolysis to placebo for acute stroke between 4.5 and 9 hours after symptom onset or for wake-up stroke that had perfusion-diffusion MRI or computed tomography (CT) perfusion imaging. Three trials, EXTEND, ECASS-4-EXTEND, and EPITHET, met eligibility criteria and contributed data fo…