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Updated: Jul 14, 2026
10:34
Double Direct Injection of Blood into the Cisterna Magna as a Model of Subarachnoid Hemorrhage
Published on: August 30, 2020
Aneurysmal Versus "Benign" Perimesencephalic Subarachnoid Hemorrhage.
Anas Alrohimi1,2, Mark A Davison1, Abhi Pandhi1
1Cerebrovascular Center Neurologic Institute Cleveland Clinic Foundation Cleveland OH United States.
Stroke (Hoboken, N.J.)
|January 26, 2026
Summary
Perimesencephalic subarachnoid hemorrhage can involve ruptured aneurysms in 6.2% of cases, often detected via cerebral angiography. Underlying aneurysms, hydrocephalus, and symptomatic vasospasm are linked to poorer outcomes.
Area of Science:
- Neurology
- Neurosurgery
- Radiology
Background:
- Perimesencephalic subarachnoid hemorrhage (PSAH) is often considered benign, but data on underlying ruptured aneurysms and complications are limited.
- Understanding these factors is crucial for optimizing patient management and outcomes.
Purpose of the Study:
- To investigate the rate of underlying ruptured aneurysms in PSAH.
- To identify common complications and their association with patient outcomes.
- To evaluate the clinical significance of hydrocephalus and vasospasm in PSAH.
Main Methods:
- Retrospective analysis of 81 patients diagnosed with PSAH between 2007 and 2022.
- Review of diagnostic imaging including computed tomography angiography and digital subtraction angiography.
- Assessment of complications such as vasospasm and hydrocephalus.
- Evaluation of functional status using the modified Rankin scale.
Main Results:
- An underlying ruptured aneurysm was identified in 6.2% of patients, with 3.7% requiring cerebral angiography for detection.
- Vasospasm occurred in 31% of patients, predominantly asymptomatic (84%). Symptomatic vasospasm was more frequent in patients with aneurysms (40% vs. 2.6%).
- Hydrocephalus occurred in 10% of patients, all within 24 hours. Poor functional status (modified Rankin scale 0-2) was associated with underlying aneurysms, hydrocephalus, and symptomatic vasospasm.
Conclusions:
- PSAH is associated with underlying aneurysms in a small percentage of cases, necessitating thorough angiographic evaluation.
- Hydrocephalus and symptomatic vasospasm are significant predictors of poor outcomes.
- Non-aneurysmal PSAH without hydrocephalus may allow for less intensive monitoring and shorter hospital stays.
Keywords:
aneurysmdigital subtraction angiographyhydrocephalusperimesencephalic subarachnoid hemorrhagevasospasmMore Related Videos
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