Related Experiment Video
Updated: May 9, 2026

Pre-Chiasmatic, Single Injection of Autologous Blood to Induce Experimental Subarachnoid Hemorrhage in a Rat Model
Published on: June 18, 2021
Sphenoid and subdural hemorrhage as a presenting sign of ruptured clinoid aneurysm
Daniel Shepherd1, Joseph Kapurch, Sudhir Datar
1Department of Neurologic Surgery, Mayo Clinic, 200 First St. SW, Rochester, MN, 55905, USA.
Background:
Aneurysm rupture presenting as an isolated or pure subdural hematoma (SDH) without subarachnoid hemorrhage is an extremely rare radiographic presentation. We present a case of a ruptured internal carotid artery aneurysm with a pure SDH and concurrent sphenoid sinus hemorrhage.
Methods:
Case report and review of the literature.
Results:
We describe a case of a 48-year-old right-handed woman found comatose brought by emergency medical services to an outside hospital. A non-contrast head CT scan demonstrated bilateral acute SDHs without evidence of intraparenchymal or subarachnoid hemorrhage. A CT angiogram of the head showed a focal hyperdensity in the distal left internal carotid artery (ICA) and was confirmed by conventional cerebral angiography to be a 7-mm left supraclinoid ICA aneurysm. On repeat CT scan a new hemorrhage was seen in the sphenoid sinus indicating a re-bleeding. The aneurysm was treated with coil embolization and complete occlusion was confirmed with subsequent angiograms. The patient had an eventful hospital course complicated by a Takotsubo cardiomyopathy and pulmonary edema. She was medically treated with successful recovery of her cardiopulmonary function. She remained markedly disabled and was transferred to an inpatient rehabilitation center for continued convalescence.
Conclusions:
Acute subdural hematoma may be due to a ruptured clinoid carotid aneurysm. Acute hemorrhage into the sphenoid sinus can be an important clue.
Related Concept Videos
Hemorrhagic Stroke l: Introduction
Hemorrhagic Stroke ll: Pathophysiology
Increased Intracranial Pressure l: Introduction
Aneurysm II: Clinical Manifestations and Diagnostic Studies
Increased Intracranial Pressure ll: Pathophysiology
Cerebral Edema ll: Pathophysiology

