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Double Direct Injection of Blood into the Cisterna Magna as a Model of Subarachnoid Hemorrhage
Published on: August 30, 2020
Circulatory and vascular changes after aneurysmal subarachnoid hemorrhage
1Department of Surgery, University of Toronto, ON, Canada.
Journal of Neurosurgical Sciences
|December 27, 2011
Summary
Delayed cerebral ischemia (DCI) after subarachnoid hemorrhage (SAH) is poorly understood, with vasospasm not fully explaining outcomes. This review examines macrovascular and microvascular changes and treatments for DCI.
Area of Science:
- Neuroscience
- Neurology
- Critical Care Medicine
Background:
- Delayed cerebral ischemia (DCI) affects ~30% of aneurysmal subarachnoid hemorrhage (SAH) patients, leading to neurological deficits, disability, and death.
- Traditional DCI management focused on angiographic vasospasm, but clinical trials yielded disappointing results, failing to improve patient outcomes.
- Emerging evidence suggests vasospasm alone cannot explain DCI, prompting investigation into other pathogenetic mechanisms.
Purpose of the Study:
- To review and contrast macrovascular and microvascular alterations following SAH.
- To provide an overview of current and potential therapeutic strategies for DCI.
Main Methods:
- Literature review and synthesis of existing research on DCI pathogenesis and treatment.
- Comparative analysis of macrovascular (angiographic vasospasm) and microvascular (e.g., constriction, BBB breakdown) changes.
- Overview of established and experimental DCI treatment modalities.
Main Results:
- Clinical trials targeting angiographic vasospasm have largely failed to prevent DCI or improve outcomes.
- Novel DCI theories highlight microvascular dysfunction, including constriction, cortical spreading depression, blood-brain barrier breakdown, and microthrombosis.
- A significant gap exists between understanding macrovascular changes and the complex microvascular events contributing to DCI.
Conclusions:
- DCI pathogenesis is multifactorial, involving complex microvascular changes beyond simple vasospasm.
- Future DCI research and treatment strategies must address these microvascular dysfunctions.
- A comprehensive understanding of both macro- and microvascular alterations is crucial for developing effective DCI therapies.
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