Gamma Knife stereotactic radiosurgery
for arteriovenous malformations
Overview
Gamma Knife stereotactic radiosurgery is a successful alternative treatment for arteriovenous malformations (AVMs) when:
- Traditional surgery is not possible
- In patients who prefer a non-invasive procedure for a small AVM.
Gamma knife radiation closes off the abnormal blood vessels of the AVM by causing the inner walls to scar and eventually close.
Gamma Knife radiosurgery is also offered to patients when the AVM is hard to reach in the brain.
When used for treating larger AVMs, several Gamma Knife surgery sessions are often needed.
The Gamma Knife radiosurgery:
- Precisely targets the blood vessels without compromising the surrounding areas
- Damages the cells in the lining of the blood vessel
The healing process then causes the lining to thicken until it blocks off blood flow through that vessel.
While the arteriovenous malformation does not disappear completely, it becomes something like a scar.
Eventually, the vessels close and shrivel over a period of 3-5 years after Gamma Knife treatment.
According to The Hearing Journal, “Gamma Knife stereotactic radiosurgery is a highly effective, integrated solution for the non-invasive treatment of acoustic neuroma. It allows patients the option of tumour control versus tumour removal, thereby avoiding the need for brain surgery.”
Internationally proven treatment
Arteriovenous malformations (AVMs) can be treated using Gamma Knife radiosurgery when they form in the brain.
Gamma Knife radiosurgery has a 70-85% success rate after 3-5 years. It is generally a safe treatment when treating small AVMs that are less than 3 cm.
As a rule, the smaller the arteriovenous malformation, the better the outcomes.
For AVMs between one and two centimetres, results with Gamma Knife treatment can be as high as 95%.
If larger AVMs are treated using the Gamma Knife, multiple treatment sessions may be required over time.
Success is dependent on:
- the size of the arteriovenous malformation
- its location
Gamma Knife radiosurgery is used when the location of the AVM makes traditional surgery too risky.
- Facial nerve impairment is experienced by less than 2 % of Gamma Knife-treated patients
- Trigeminal nerve impairment (mild to severe facial pain) is experienced by only 1.8 % (18 out of a thousand) Gamma Knife-treated patients
- After Gamma Knife radiosurgery, vertigo and imbalance, another possible side-effect of treatment, affects just 1.5 % (15 out of a thousand) of patients
For those patients with an arteriovenous malformation who are experiencing seizures before Gamma Knife radiosurgery, there is a reduction of between a third and two thirds in these pre-treatment seizures (28–66.7%).
While Gamma Knife surgery is considered safe, there can be a small risk of bleeding (1.8-5%) while the abnormal blood vessel closes. However, this is the same as the rate in untreated patients.
