Related Experiment Video
Updated: May 11, 2026
10:34
Double Direct Injection of Blood into the Cisterna Magna as a Model of Subarachnoid Hemorrhage
Published on: August 30, 2020
Nonaneurysmal subarachnoid hemorrhage after udenafil intake
Eun-Kee Bae1, Jong-Hyeon Ahn, Jeong-Jin Park
1Department of Neurology, Inha University Hospital, Incheon, Korea.
Summary
Phosphodiesterase 5 inhibition may trigger perimesencephalic subarachnoid hemorrhage. This rare event may be linked to venous hypertension, potentially associated with vein of Galen stenosis.
Area of Science:
- Neurology
- Pharmacology
Background:
- Phosphodiesterase 5 (PDE5) inhibitors are widely used for erectile dysfunction.
- Severe headache is a potential side effect of PDE5 inhibitors.
Observation:
- A 67-year-old man experienced a severe headache after taking 50 mg of udenafil, a novel PDE5 inhibitor.
- Brain CT revealed acute subarachnoid hemorrhage in the basal cisterns.
Findings:
- No cerebral artery aneurysms were identified.
- Magnetic resonance venography suggested possible vein of Galen stenosis.
- The subarachnoid hemorrhage was localized anterior to the midbrain and pons.
Implications:
- This case suggests a potential link between PDE5 inhibition and perimesencephalic subarachnoid hemorrhage.
- Venous hypertension, possibly due to vein of Galen stenosis, may be a contributing factor.
- Further research is needed to confirm the association between PDE5 inhibitors and this type of hemorrhage.
Related Concept Videos
01:28Treatment for Pulmonary Arterial Hypertension: Phosphodiesterase Inhibitors
Phosphodiesterase 5 (PDE5) inhibitors are potent enzymes that function to hydrolyze cyclic nucleotides to their corresponding 5' monophosphates. Their unique biochemical properties have been applied in treating Pulmonary Arterial Hypertension (PAH).
Among the PDE5 inhibitors, sildenafil (Revatio) stands out as a competitive and selective inhibitor. It operates by elevating cellular levels of cGMP and augmenting signaling through the cGMP-PKG pathway, promoting vasodilation. Upon oral...
Among the PDE5 inhibitors, sildenafil (Revatio) stands out as a competitive and selective inhibitor. It operates by elevating cellular levels of cGMP and augmenting signaling through the cGMP-PKG pathway, promoting vasodilation. Upon oral...
01:17Hemorrhagic Stroke l: Introduction
A hemorrhagic stroke is an acute neurological event that occurs when a weakened cerebral blood vessel ruptures, allowing blood to accumulate within or around the brain. The sudden release of blood forms a focal hematoma that increases intracranial pressure, displaces neural tissue, and can obstruct cerebrospinal fluid pathways. These effects may be compounded by intraventricular extension of the hemorrhage, cerebral edema, or compression of adjacent structures, all of which contribute to...
01:26Aneurysm III: Interprofessional Care
Aneurysm management involves either conservative medical therapy or surgical intervention, depending on the size and symptoms of the aneurysm. Conservative management is generally reserved for smaller, asymptomatic aneurysms, while larger or symptomatic aneurysms often necessitate surgical repair.Conservative Medical TherapyFor small, asymptomatic aneurysms, particularly abdominal aortic aneurysms (AAA) less than 5.5 centimeters in diameter, conservative medical therapy is recommended. This...
01:22Aneurysm IV: Nursing Management
Vigilant monitoring for aneurysm rupture is essential for patients undergoing aortic surgery.Preoperative Nursing ManagementContinuously monitor the patient for manifestations of aneurysm rupture, such as pallor, weakness, tachycardia, hypotension, abdominal, back, groin, or periumbilical pain, changes in consciousness, and a pulsating abdominal mass. Regularly assess the patient's peripheral pulses.Instruct the patient to consume a clear liquid diet the day before surgery and administer...
01:30Aneurysm I: Introduction
An aortic aneurysm is a localized outpouching or dilation at a weak point in the artery wall. It may involve different parts of the aorta, such as the abdominal aorta, aortic arch, or thoracic aorta.Etiological factorsSeveral disorders are associated with aortic aneurysms.Congenital causes, such as primary connective tissue disorders like Marfan syndrome, impact the integrity and strength of connective tissues, notably affecting the aorta. Marfan syndrome is a genetic disorder that specifically...
01:21Aneurysm II: Clinical Manifestations and Diagnostic Studies
Thoracic, aortic arch and abdominal aneurysms are significant vascular conditions that can present with various clinical manifestations and lead to serious complications. Understanding these manifestations and the appropriate diagnostic studies is essential for effective management and treatment.Thoracic Aortic AneurysmsThoracic aortic aneurysms often remain asymptomatic until they reach a size that impinges on adjacent structures. They typically cause deep, diffuse chest pain that radiates to...