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Updated: Aug 20, 2025
A Volumetric Method for Quantification of Cerebral Vasospasm in a Murine Model of Subarachnoid Hemorrhage
Published on: July 28, 2018
Cervical sympathectomy to treat cerebral vasospasm: a scoping review
Anna Maria Bombardieri1, Boris D Heifets2, Miriam Treggiari3
1Anesthesiology and Perioperative Medicine, Stanford University School of Medicine, Stanford, California, USA abomba@stanford.edu.
Insights
Cervical sympathetic block (CSB) shows promise for treating cerebral arterial vasospasm (CAV) after subarachnoid hemorrhage. While current treatments are limited, CSB may improve cerebral blood flow and neurological outcomes, warranting further research.
Area of Science:
- Neurology
- Vascular Surgery
- Critical Care Medicine
Background:
- Delayed cerebral ischemia (DCI) is a major cause of death after aneurysmal subarachnoid hemorrhage (aSAH).
- Cerebral arterial vasospasm (CAV) is a primary driver of DCI, with current treatments being invasive and having limited efficacy.
- Cervical sympathetic block (CSB) presents an underappreciated therapeutic option for CAV.
Purpose of the Study:
- To conduct a comprehensive review of preclinical and human literature on CSB for CAV.
- To evaluate the potential of CSB as a treatment for CAV in aSAH patients.
Main Methods:
- Scoping review following PRISMA-ScR guidelines.
- Extensive literature search across Embase, PubMed, Cochrane, Scopus, and Web of Science until February 2022.
- Inclusion of six human and six experimental studies, analyzing various imaging modalities and outcomes.
Main Results:
- Human studies, mostly observational, indicated neurological improvement and increased cerebral arterial diameter post-CSB.
- Digital subtraction angiography showed improved cerebral perfusion, while Transcranial Doppler revealed a 15% decrease in velocities, suggesting vasodilation.
- Animal studies confirmed that sympathetic system ablation leads to cerebral vasodilation and reduced vasospasm incidence.
Conclusions:
- CSB appears to be a viable option for treating and preventing CAV/DCI in aSAH patients.
- Existing studies are heterogeneous, predominantly observational, and feature small sample sizes.
- Further research is essential to standardize CSB techniques and definitively establish its effectiveness.
Background/Importance:
Delayed cerebral ischemia (DCI) is the second-leading cause of death and disability in patients with aneurysmal subarachnoid hemorrhage (aSAH), and is associated with cerebral arterial vasospasm (CAV). Current treatments for CAV are expensive, invasive, and have limited efficacy. Cervical sympathetic block (CSB) is an underappreciated, but potentially highly effective therapy for CAV.
Objective:
To provide a comprehensive review of the preclinical and human literature pertinent to CSB in the context of CAV.
Evidence Review:
This study followed Preferred Reporting Items for Systematic Reviews and Meta-Analyses Extension for Scoping Reviews guidelines. We conducted a literature search using Embase, PubMed, Cochrane Database of Systematic Reviews, Cochrane Central Register of Controlled Trials, Scopus and Web of Science until February 2022, to identify abstracts, conference proceedings, and full-text papers pertinent to cervical sympathectomy and CAV in animal/adult patients.
Findings:
We included six human and six experimental studies. Human studies were mostly prospective observational, except one retrospective and one randomized clinical trial, and used various imaging modalities to measure changes in arterial diameter after the block. Studies that used digital subtraction angiography showed an improvement in cerebral perfusion without change in vessel diameter. Transcranial Doppler studies found an approximately 15% statistically significant decrease in velocities consistent with arterial vasodilatation. Overall, the results suggest an increase in cerebral arterial diameter and neurological improvement in patients receiving a CSB. Animal studies demonstrate that sympathetic system ablation vasodilates cerebral vasculature and decreases the incidence of symptomatic vasospasm.
Conclusions:
This scoping review suggests that CSB may be a viable option for treatment and prevention of CAV/DCI in patients with aSAH, although the included studies were heterogeneous, mostly observational, and with a small sample size. Further research is needed to standardize the technique and prove its effectiveness to treat patients suffering of CAV/DCI after aSAH.
