An arteriovenous malformation (AVM) is a tangle of blood vessels in which arteries connect directly to veins. An arteriovenous fistula is a direct abnormal link of the same kind. Both can bleed, cause seizures, or steal blood from healthy brain. Treatment aims to close the abnormal connection safely and may combine more than one method.
Who it may help
- A bleed in the brain with no clear cause
- New seizures
- Weakness, vision loss or other neurological symptoms
- A pulsing sound in the ear (pulsatile tinnitus)
- A malformation seen on a scan done for another reason
Conditions treated
- Brain AVMs of different grades
- Dural arteriovenous fistulas
- Spinal AVMs and fistulas
- Vein of Galen malformations
- Post-traumatic fistulas
- AVMs in children
Treatment options
- Microsurgical removal Suited to AVMs that sit near the surface and are small to medium in size.
- Endovascular embolisation A catheter is used to block the abnormal vessels with glue or coils.
- Combined or staged treatment Embolisation followed by surgery, for complex lesions.
- Radiosurgery Focused radiation for small or deep AVMs, arranged through a partner centre.
- Observation Some lesions are best watched with imaging when treatment risks outweigh benefits.
Before the procedure
- Digital subtraction angiography (DSA) for detailed mapping
- Functional MRI or EEG if seizures are present
- Grading of the AVM to estimate risk
- A thorough conversation about risks, benefits and alternatives
Recovery: what to expect
- Embolisation: often 1 to 2 days in hospital.
- Surgery: about 4 to 6 days, depending on the location.
- Observation in intensive care for the first day or two.
- The wound heals over 10 to 14 days.
- A follow-up angiogram at about 6 weeks, 6 months and 1 year to confirm that the AVM is closed.
These are typical timings. Your own plan depends on your condition, your general health and the operation chosen, and Dr. Chakraborty will go through it with you.
Risks to know about
Every operation carries risk. The ones most relevant here are:
- Bleeding or stroke during or after treatment
- New weakness, vision or speech problems depending on the site
- Seizures
- An AVM that is not fully closed, needing further treatment
- Radiosurgery works slowly over years and protection from bleeding is not immediate
Your own risks depend on your health and your scans, and are explained in detail before you decide on anything.
Common questions
Does every AVM need treatment?
Not always. The decision depends on size, location, bleeding history and symptoms.
Can an AVM be cured?
Yes, if it is fully removed or closed. Long-term follow-up with imaging is still needed.
What if the AVM is deep or high-risk?
Radiosurgery or staged treatment may be safer than an operation. These choices are discussed with you.
Are fistulas more dangerous than AVMs?
Some, such as dural fistulas, can cause bleeding or brain swelling and are treated early.
This page is general information to help you prepare for a consultation. It is not medical advice and does not replace an examination. Every plan is made for the individual patient.