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Updated: Jun 24, 2026
09:14
Pre-Chiasmatic, Single Injection of Autologous Blood to Induce Experimental Subarachnoid Hemorrhage in a Rat Model
Published on: June 18, 2021
Clinical differences between angiographically negative, diffuse subarachnoid hemorrhage and perimesencephalic
Ferdinand K Hui1, Luis M Tumialán, Tomoko Tanaka
1Department of Radiology, Emory University, Atlanta, GA, USA. huif@ccf.org
Neurocritical Care
|March 12, 2009
Summary
Diffuse subarachnoid hemorrhage (d-SAH) without a clear cause on angiography is linked to worse outcomes. Patients with d-SAH face higher risks of vasospasm and hydrocephalus, necessitating closer monitoring.
Area of Science:
- Neurology
- Neurosurgery
- Radiology
Background:
- Subarachnoid hemorrhage (SAH) is a critical neurological condition.
- Angiographically negative SAH presents diagnostic and management challenges.
- Distinguishing between perimesencephalic (p-SAH) and diffuse (d-SAH) subtypes is crucial.
Purpose of the Study:
- To identify prognostic factors for vasospasm, hydrocephalus, and clinical outcomes.
- To compare outcomes between perimesencephalic (p-SAH) and diffuse (d-SAH) subtypes of angiographically negative SAH.
- To establish risk stratification for patients with d-SAH.
Main Methods:
- Retrospective review of 94 patients with angiographically negative SAH over 6 years.
- Stratification into perimesencephalic (p-SAH) and diffuse (d-SAH) subtypes based on CT findings.
- Analysis of vasospasm, hydrocephalus, treatment requirements, and clinical outcomes.
Main Results:
- Diffuse SAH (d-SAH) occurred in 63 patients, perimesencephalic SAH (p-SAH) in 31.
- d-SAH patients had significantly higher rates of hydrocephalus (50.8% vs. 9.6%) and need for ventricular drainage (41% vs. 9.6%).
- d-SAH was associated with increased symptomatic vasospasm (28.6% vs. 9.6%) and lower rates of complete recovery (76% vs. 96.7%).
Conclusions:
- The angiographically negative diffuse SAH pattern indicates a worse clinical presentation and outcome.
- Patients with d-SAH have an elevated risk of vasospasm and hydrocephalus requiring aggressive management.
- Increased surveillance is recommended for patients diagnosed with d-SAH.
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