Bücke P Pérez MA Hellstern V AlMatter M Bäzner H Henkes H 2018 BACKGROUND AND PURPOSE Mechanical thrombectomy in acute ischemic stroke within 6 hours of symptom onset is effective and safe. However, in many patients, information on the beginning of symptoms is not available. Patients can be divided into those with wake-up stroke and daytime-unwitnessed stroke. Evidence on outcome and complications after mechanical thrombectomy in wake-up stroke and daytime-unwitnessed stroke is rare. A potential beneficial effect of mechanical thrombectomy in selected patients with wake-up stroke or daytime-unwitnessed stroke is suspected. MATERIALS AND METHODS We analyzed 1073 patients with anterior circulation stroke undergoing mechanical thrombectomy between 2010 and 2016. Patients with wake-up stroke and daytime-unwitnessed stroke were compared with controls receiving mechanical thrombectomy as the standard of care. We assessed good functional outcome (mRS ≤ 2 at 3 months), mortality rates, and frequencies of symptomatic intracranial hemorrhage. Subgroup analyses tried to detect influences of patient selection via further imaging modalities (MR imaging, CTP; wake-up stroke [advanced], daytime-unwitnessed stroke [advanced]) on outcome and safety. RESULTS There was no significant difference in good functional outcome between patients with wake-up stroke and controls (35.9% versus 38.3%, P = .625). Outcome in patients with daytime-unwitnessed stroke was inferior compared with controls (27.3%, P = .007). Groups did not differ in all-cause mortality at day 90 (P = .224) and the rate of symptomatic intracranial hemorrhage (P = .292). Advanced imaging improved the frequency of good functional outcome (non-wake-up stroke [advanced] versus wake-up stroke [advanced]: OR, 2.92; 95% CI, 1.32-6.45; non-daytime-unwitnessed stroke [advanced] versus daytime-unwitnessed stroke [advanced]: OR, 2.09; 95% CI, 1.03-4.25) with an additional reduction in all-cause mortality (non-daytime-unwitnessed stroke [advanced] versus daytime-unwitnessed stroke [advanced]: OR, 0.42; 95% CI, 0.20-0.88). CONCLUSIONS Mechanical thrombectomy in selected patients with wake-up stroke allows a good functional outcome comparable with that of controls. Outcome after mechanical thrombectomy in daytime-unwitnessed stroke seems to be inferior compared with that in controls. Advanced imaging modalities may increase the frequency of good functional outcome in both patients with wake-up stroke and daytime-unwitnessed stroke. application/pdf https://sonar.ch/global/documents/10536 eng info:eu-repo/semantics/altIdentifier/doi/10.3174/ajnr.A5540 info:eu-repo/semantics/altIdentifier/pmid/29439123 info:eu-repo/semantics/openAccess AJNR. American journal of neuroradiology. - 2018 Aged Female Humans Intracranial Hemorrhages Male Middle Aged Patient Selection Stroke Thrombectomy Time-to-Treatment Treatment Outcome Endovascular Thrombectomy in Wake-Up Stroke and Stroke with Unknown Symptom Onset. http://purl.org/coar/resource_type/c_6501