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A Magnetic Resonance Imaging Protocol for Stroke Onset Time Estimation in Permanent Cerebral Ischemia
Published on: September 16, 2017
Wake-up stroke: clinical and neuroimaging characteristics
Gisele S Silva1, Fabricio O Lima, Erica C S Camargo
1Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA. giselesampaio @ hotmail.com
Cerebrovascular Diseases (Basel, Switzerland)
|February 5, 2010
Summary
Wake-up strokes, a common presentation of ischemic stroke, often lack a clear onset time. Advanced brain imaging like CT perfusion (CTP) can identify salvageable brain tissue, potentially expanding treatment eligibility.
Area of Science:
- Neurology
- Radiology
- Emergency Medicine
Background:
- Approximately 25% of ischemic stroke patients present with neurological deficits upon waking.
- Determining the exact time of symptom onset is challenging in these wake-up stroke cases.
- Brain imaging offers a potential solution to assess ischemia duration and identify viable brain tissue.
Purpose of the Study:
- To evaluate the utility of CT angiography and CT perfusion (CTP) in patients with acute ischemic stroke.
- To compare imaging findings across stroke onset groups: known onset, indefinite onset, and wake-up strokes.
- To investigate the prevalence of CTP mismatch and large-vessel occlusions in different stroke onset groups.
Main Methods:
- Prospective evaluation of consecutive acute ischemic stroke patients.
- Performance of CT angiography and CTP within 24 hours of symptom onset.
- Classification of patients into 'known onset', 'indefinite onset', and 'wake-up stroke' categories.
Main Results:
- Ischemic lesion volumes were significantly larger in patients with indefinite-onset strokes (p = 0.04).
- Frequencies of CT perfusion (CTP) mismatch were similar across all onset groups (p = 0.9).
- Rates of large-vessel intracranial occlusions did not differ significantly between groups (p = 0.2).
Conclusions:
- Wake-up stroke patients exhibit a notable prevalence of CTP mismatch and intracranial artery occlusions.
- Arterial and perfusion imaging are crucial for evaluating wake-up stroke patients.
- Imaging-based protocols may enable expanded thrombolysis indications for patients with uncertain stroke onset times.
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