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Double Direct Injection of Blood into the Cisterna Magna as a Model of Subarachnoid Hemorrhage
Published on: August 30, 2020
Venous drainage patterns in perimesencephalic nonaneurysmal subarachnoid hemorrhage
Haruki Yamakawa1, Naoyuki Ohe, Hirohito Yano
1Department of Neurosurgery, Gifu University Graduate School of Medicine, Yanagido 1-1, Gifu 501-1194, Japan. noritake31513@hotmail.com <noritake31513@hotmail.com>
Clinical Neurology and Neurosurgery
|April 25, 2008
Summary
Perimesencephalic nonaneurysmal subarachnoid hemorrhage (P-SAH) may stem from primitive venous drainage patterns and strenuous exertion like the Valsalva maneuver. These factors appear to predispose individuals to P-SAH, unlike aneurysmal subarachnoid hemorrhage (A-SAH).
Area of Science:
- Neurology
- Vascular Imaging
- Radiology
Background:
- The exact cause of perimesencephalic nonaneurysmal subarachnoid hemorrhage (P-SAH) remains unclear.
- Investigating venous drainage patterns may elucidate P-SAH etiology.
Purpose of the Study:
- To compare venous drainage patterns in patients with P-SAH versus aneurysmal subarachnoid hemorrhage (A-SAH).
- To identify potential predisposing factors for P-SAH.
Main Methods:
- Retrospective analysis of venograms from 18 P-SAH patients and 112 A-SAH patients.
- Focus on abnormalities and anatomical variants of the basal vein of Rosenthal (BVR).
Main Results:
- Patients with P-SAH exhibited significantly more primitive BVR configurations compared to A-SAH patients (P<0.05).
- Strenuous physical exertion, including Valsalva maneuver components, caused 69.2% of P-SAH cases, significantly higher than in A-SAH (14.3%, p<0.05).
Conclusions:
- Failure of longitudinal venous anastomoses and strenuous exertion are implicated in P-SAH etiology.
- These findings highlight potential predisposing factors for P-SAH.
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