Cerebral arteriovenous malformation
A cerebral arteriovenous malformation is an abnormal connection between the arteries and veins in the brain that usually forms before birth.
AVM - cerebral
The cause of cerebral arteriovenous malformation (AVM) is unknown. The condition occurs when arteries in the brain connect directly to nearby veins without having the normal vessels (capillaries) between them.
AVMs vary in size and location in the brain.
An AVM rupture occurs because of pressure and damage to blood vessel tissue. This allows blood to leak (hemorrhage) into the brain or surrounding tissues, and reduces blood flow to the brain.
Cerebral AVMs are rare. Although the condition is present at birth, symptoms may occur at any age. Hemorrhages occur most often in people ages 15 to 20. It can also occur later in life. Some people with an AVM also have brain aneurysms.
In about half of people with AVMs, the first symptoms are those of a stroke caused by bleeding in the brain.
Symptoms of an AVM that is bleeding are:
Symptoms due to pressure on one area of the brain include:
Exams and Tests
A complete physical examination and neurologic examination are needed.
Tests that may be used to diagnose an AVM include:
Finding the best treatment for an AVM that is found on an imaging test but is not causing any symptoms can be difficult. Your doctor will discuss with you:
Your doctor may discuss different factors that may increase your risk of bleeding, including:
A bleeding AVM is a medical emergency. The goal of treatment is to prevent further complications by controlling the bleeding and seizures and, if possible, removing the AVM.
Three surgical treatments are available. Some treatments are used together.
Open brain surgery removes the abnormal connection through an opening made in the skull.
Embolization (endovascular treatment):
Anticonvulsant medicines are usually prescribed if seizures occur.
1 in 10 people whose first symptom is excessive brain bleeding will die. Some people may have permanent seizures and brain and nervous system problems.
AVMs that do not cause symptoms by the time people reach their late 40s or early 50s are more likely to remain stable and rarely cause symptoms.
Complications may include:
Possible complications of open brain surgery include:
When to Contact a Medical Professional
Go to the emergency room or call the local emergency number (such as 911) if you have:
Also seek medical attention if you have a first-time seizure, because AVM may be the cause of seizures.
Kase CS. Vascular diseases of the nervous system: Intracerebral hemorrhage. In: Daroff RB, Fenichel GM, Jankovic J, Mazziotta JC, eds. Bradley's Neurology in Clinical Practice. 6th ed. Philadelphia, PA: Elsevier Saunders; 2012:chap 51B.
Laakso A, Dashti R, Juvela S, Niemelä M, Hernesniemi J. Natural history of arteriovenous malformations: presentation, risk of hemorrhage and mortality. Acta Neurochir Suppl. 2010;107:65-69. PMID 19953373. www.ncbi.nlm.nih.gov/pubmed/19953373
Spagnuolo E. Surgical management of cerebral arteriovenous malformations. In: Quinones-Hinojosa A, ed. Schmidek and Sweet Operative Neurosurgical Techniques. 6th ed. Philadelphia, PA: Elsevier Saunders; 2012:chap 83.
Review Date: 11/5/2014
Reviewed By: Joseph V. Campellone, M.D., Division of Neurology, Cooper University Hospital, Camden, NJ. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the A.D.A.M. Editorial team.
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