Related Experiment Video
Updated: Aug 9, 2026
10:41
Analysis of Cerebral Vasospasm in a Murine Model of Subarachnoid Hemorrhage with High Frequency Transcranial Duplex Ultrasound
Published on: June 3, 2021
Understanding late-window cerebral vasospasm in aneurysmal subarachnoid hemorrhage
Omar Alwakaa1, Thomas Fodor1, James Devanney2
1Department of Neurosurgery, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA.
Clinical Neurology and Neurosurgery
|August 7, 2026
Summary
Late-window cerebral vasospasm, occurring after 10 days, affects about 14% of patients with aneurysmal subarachnoid hemorrhage. Higher Fisher grade and delayed aneurysm treatment are key predictors, suggesting extended neurovascular monitoring is crucial.
Area of Science:
- Neurology
- Neurosurgery
- Radiology
Background:
- Cerebral vasospasm is a critical factor influencing neurological outcomes after aneurysmal subarachnoid hemorrhage (aSAH).
- While vasospasm typically manifests between days 3-10 post-admission, a subset of patients experience a delayed onset, the predictors of which are not well understood.
Purpose of the Study:
- To determine the incidence of late-window cerebral vasospasm (occurring >10 days post-symptom onset) in patients with aSAH.
- To identify independent clinical and radiographic predictors associated with this late-onset vasospasm.
Main Methods:
- A prospectively maintained database of aSAH patients (2003-2024) was reviewed.
- Patients diagnosed with vasospasm via transcranial Doppler or CT angiography were analyzed.
- Univariable and multivariable logistic regression identified predictors of late-window vasospasm (p < 0.05).
Main Results:
- Of 370 aSAH patients, 192 (51.9%) had vasospasm; 27 (14.1%) presented with late-window vasospasm.
- Univariable analysis linked female sex, smoking, surgical treatment, Fisher grade, and delayed aneurysm treatment (>48h) to late-window vasospasm.
- Multivariable analysis confirmed higher Fisher grade (aOR 2.34) and delayed aneurysm treatment (aOR 8.86) as independent predictors.
Conclusions:
- Approximately 14% of patients with vasospasm following aSAH experience a late-onset presentation.
- Higher Fisher grade and delayed aneurysm treatment are significant independent predictors of late-window vasospasm.
- Extended neurovascular surveillance beyond 10 days is recommended for patients with these risk factors.
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