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Optimized Management of Endovascular Treatment for Acute Ischemic Stroke
Published on: January 18, 2018
Intravenous thrombolysis in ischemic stroke with unknown onset using CT perfusion
E Cortijo1, P García-Bermejo, A I Calleja
1Stroke Unit, Department of Neurology and Medicine, Hospital Clínico Universitario, Universidad de Valladolid, Valladolid, Spain.
Acta Neurologica Scandinavica
|July 16, 2013
Summary
Acute ischemic stroke patients with unknown onset time, presenting over 4.5 hours from last-seen-normal, are eligible for computed tomography perfusion (CTP)-guided thrombolysis. These patients show similar outcomes to those with witnessed onset, suggesting broader treatment eligibility.
Area of Science:
- Neurology
- Emergency Medicine
- Radiology
Background:
- Acute ischemic stroke patients presenting >4.5 hours from last-seen-normal (LSN) with unknown onset are typically excluded from intravenous thrombolysis.
- This study investigates if this subgroup differs from patients with witnessed onset regarding treatment eligibility and response.
Purpose of the Study:
- To compare the eligibility and outcomes of acute ischemic stroke patients presenting >4.5 hours from LSN with unknown onset versus witnessed onset for computed tomography perfusion (CTP)-guided intravenous thrombolysis.
Main Methods:
- Prospective study of acute non-lacunar middle cerebral artery (MCA) ischemic stroke patients presenting >4.5 hours from LSN.
- Patients underwent multimodal CT; eligibility for i.v. thrombolysis was assessed using CTP criteria.
- Comparison of thrombolysis eligibility and outcomes between patients with unknown versus witnessed stroke onset.
Main Results:
- Of 147 patients, 73 had unknown onset and 74 had witnessed onset.
- Eligibility for CTP-guided thrombolysis was similar (44% vs 50%, P=0.7).
- Outcomes including early neurological improvement, recanalization, hemorrhagic transformation, and 3-month functional outcome did not differ significantly between groups.
Conclusions:
- Delayed acute ischemic stroke patients with unknown onset time are comparable to those with witnessed onset regarding eligibility for CTP-guided i.v. thrombolysis.
- The findings support considering CTP-guided thrombolysis for selected patients with unknown stroke onset beyond the 4.5-hour window.
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