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Pretruncal nonaneurysmal subarachnoid hemorrhage causing basilar artery vasospasm
Wesley Hsu1, Gustavo Pradilla, Ira M Garonzik
1Department of Neurosurgery, The Johns Hopkins University School of Medicine, Johns Hopkins Medical Institutions, Meyer Bldg. 8-161, 600 N. Wolfe St., Baltimore, MD 21287, USA. weshsu@jhmi.edu
Neurocritical Care
|April 28, 2010
Summary
Perimesencephalic nonaneurysmal subarachnoid hemorrhage (PNSAH) rarely involves vasospasm. This case highlights radiographic vasospasm in a PNSAH patient, necessitating careful monitoring similar to aneurysmal subarachnoid hemorrhage.
Area of Science:
- Neurology
- Neurosurgery
- Radiology
Background:
- Perimesencephalic nonaneurysmal subarachnoid hemorrhage (PNSAH) is defined by subarachnoid hemorrhage anterior to the midbrain without an identifiable aneurysm on four-vessel angiography.
- Vasospasm is a known complication of aneurysmal subarachnoid hemorrhage but is uncommon in PNSAH.
Observation:
- A patient with PNSAH developed significant radiographic vasospasm of the basilar artery.
- Initial angiography on hospital day two showed no abnormality, but repeat imaging on hospital day eight revealed basilar artery stenosis consistent with vasospasm.
- The patient remained neurologically intact throughout the observation period.
Findings:
- A subsequent angiogram on hospital day 15 showed resolving vasospasm.
- No source for the initial hemorrhage was identified.
- The patient experienced an excellent clinical course with no long-term sequelae.
Implications:
- While PNSAH typically has a favorable prognosis, the rare occurrence of vasospasm warrants careful clinical observation.
- Monitoring for vasospasm in PNSAH patients should be comparable to that for aneurysmal subarachnoid hemorrhage until an aneurysm is definitively ruled out and vasospasm resolves.
- This case underscores the importance of serial imaging in managing PNSAH when vasospasm is suspected or identified.
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