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Updated: May 21, 2026
Double Direct Injection of Blood into the Cisterna Magna as a Model of Subarachnoid Hemorrhage
Published on: August 30, 2020
Aggressive CSF diversion reverses delayed cerebral ischemia in aneurysmal subarachnoid hemorrhage: a case report
Jennifer E Fugate1, Alejandro A Rabinstein, Eelco F M Wijdicks
1Division of Critical Care Neurology, Mayo Clinic, Rochester, MN 55905, USA.
Background:
External ventricular drain (EVD) placement temporarily provides cerebrospinal fluid (CSF) diversion and is indicated in patients with aneurysmal subarachnoid hemorrhage (aSAH) to relieve hydrocephalus.
Methods:
Case report.
Results:
A 56-year-old woman was admitted to our hospital with aSAH complicated by acute hydrocephalus. An EVD was placed and set to 15 mmHg. After nearly 72 h, she clinically deteriorated. A computed tomography (CT) perfusion scan showed hypoperfusion in the watershed regions in both hemispheres and CT angiogram showed mild segmental arterial narrowings. After the EVD was lowered to 5 mmHg, the radiologic perfusion abnormalities and clinical symptoms resolved.
Conclusions:
We postulate a mechanism by which CSF diversion could decrease the risk of delayed cerebral ischemia after aSAH: CSF drainage at low levels of intracranial pressure (e.g., 5 mmHg) could improve blood flow in the microcirculation, and thus improve tissue perfusion.
