Arteriovenous Malformation (AVM)

An arteriovenous malformation (AVM) is a complex tangle of abnormal blood vessels in the brain that disrupts normal blood flow and oxygen circulation.

The vast majority of AVMs are present from birth but often go undetected until symptoms appear. Because they can cause bleeding, seizures and neurological damage, early diagnosis and treatment are essential.

Dr. Arias is Director of Neurovascular Surgery at HCA HealthONE Swedish

Symptoms

Seizures
Headaches
Sudden severe headache, weakness or confusion from bleeding. Call 911
Gradually worsening weakness or numbness
Problems with speech, vision or balance
No symptoms at all; some are found by chance

How an AVM is diagnosed

MRI and CT

These scans show the location and size of the AVM and any signs of past bleeding.

Cerebral angiogram

A catheter-based angiogram maps the arteries feeding the AVM and the veins draining it. This detailed picture is essential for choosing the safest treatment.

Treatments for Arteriovenous Malformation (AVM) in Denver & Fort Collins

If you or a loved one has been diagnosed with an AVM, a consultation can help you explore the options that fit you best. Early intervention is key to long-term outcomes.

Resection

Open surgery to remove the AVM, often recommended when it is accessible and has a high risk of bleeding. Recovery depends on its size and location, and many patients improve significantly.

Embolization

A minimally invasive catheter procedure that seals the AVM from within using a glue-like material. It can be used on its own or before surgery to lower the risk of bleeding.

Gamma Knife

Non-invasive, outpatient radiosurgery that targets the AVM without an incision. Best suited to small or deep AVMs, which gradually shrink and may disappear, with minimal effect on surrounding tissue.

Observation

Some AVMs that have never bled, especially in high-risk locations, may be monitored instead of treated, after a careful discussion of the risks of each approach.

Patient stories

31-year-old woman

31-year-old woman with an arteriovenous malformation that was discovered after she had a seizure. She underwent gamma knife stereotactic radiosurgery and follow-up angiography performed 3 years after treatment demonstrated complete resolution of the malformation.

Cerebral angiogram with an arrow pointing to an arteriovenous malformation before treatment — Before: Arteriovenous malformation

Cerebral angiogram three years after Gamma Knife radiosurgery showing the malformation is gone — After: Complete resolution 3 years after Gamma Knife

18-year-old man

18-year-old man with a brain hemorrhage from a ruptured arteriovenous malformation. He underwent embolization and subsequent surgical resection of the lesion. We achieved removal of the entire lesion, and 6 months after his event, he is back in school.