Ver el código de «Arteriovenous malformation»

==Background==
*Focal abnormal conglomerations of dilated arteries and veins in the brain parenchyma
**Arterial blood flows directly into draining veins without capillary beds creating high pressure channels
**May rupture, causing intracerebral hemorrhage +/- intraventricular hemorrhage.  Mechanism of rupture incompletely understood.
*Prevalence 0.14% 
*Congenital lesions
**Majority are sporadic, not familial
**Associated with Osler- Weber-Rendu disease and Sturge-Weber syndrome
*Lifelong risk of bleeding 
**2-4% per year, cumulative

==Clinical Features==
*Hemorrhage (most common)
**42-72% of clinically apparent AVMs
**Usually by age 20-49
*[[Seizures]]
*Ischemia (by vascular steal – rare)
*[[Headaches]]

==Differential Diagnosis==
*Venous angioma
*Cavernous malformation
*Capillary telangiectasia
==Diagnosis==
===Work-up===
*CT/CTA
**CT delineates acute hemorrhage, CTA to show abnormal vasculature
*MRI/MRA
**Vessels appear as abnormal flow voids
**Both better than CT for visualizing structures in relation to AVM
*Angiography
**Gold standard to evaluate the architecture including arterial feeding, venous drainage, and AVM-associated aneurysms
===Evaluation===

==Management==
*Surgical Resection
**Traditionally treatment of choice
*Radiosurgery (Gamma Knife or CyberKnife)
*Embolization (usually an adjunct treatment)
*Combination of above three in some cases
**Decision is based on AVM size, location, and patient factors

==Disposition==
*In cases of acute hemorrhage or neurological decline, obvious need for immediate neurosurgical consultation
*If patient presents with headache or seizure and lesion is then found, may simply warrant outpatient neurosurgical evaluation

==See Also==

==External Links==

==References==
<references/>

[[Category:Neurology]]
[[Category:Vascular]]