What Are The Key Facts About Gamma Knife Treatment For AVMs?

What Are The Key Facts About Gamma Knife Treatment For AVMs?

Arteriovenous malformations, commonly known as AVMs, are abnormal tangles of blood vessels in the brain where arteries connect directly to veins, bypassing the normal capillary system. This can disrupt normal blood flow and oxygen delivery, leading to a variety of neurological problems.

AVMs are relatively rare but can be serious, with risks including bleeding, seizures, or stroke. For many patients, treatment options include surgery, embolisation, or radiosurgery. One of the most effective and minimally invasive treatments is Gamma Knife radiosurgery, a precision-focused procedure that targets the AVM without the need for open brain surgery.

But what makes Gamma Knife so special for AVM treatment, and what should patients know before considering it?

How does Gamma Knife treat AVMs?

Gamma Knife radiosurgery uses highly focused beams of gamma radiation to target the AVM precisely. Unlike traditional surgery, there is no need for scalp incisions or opening the skull. The Gamma Knife device delivers multiple beams of radiation that converge on the AVM, allowing a high dose at the target while sparing surrounding healthy brain tissue.

The goal of treatment is to cause the AVM vessels to gradually close off over time, reducing the risk of bleeding. This process is slow and typically takes 12–36 months for the AVM to fully obliterate, but during this period, patients can often continue normal daily activities with minimal disruption.

Who is a candidate for Gamma Knife AVM treatment?

Not all AVMs are suitable for Gamma Knife treatment. Candidates usually include:

• Patients with small to medium-sized AVMs (typically less than three to four cm in diameter).
• AVMs located in areas of the brain that are difficult to reach with conventional surgery.
• Patients for whom surgery poses a high risk due to the AVM’s location near critical brain structures.
• Individuals who prefer a non-invasive option with shorter recovery times.

Your specialist will assess the size, location, and complexity of the AVM using imaging scans like MRI or CT angiography to determine if Gamma Knife is appropriate.

What is the Gamma Knife procedure like?

Gamma Knife treatment is an outpatient procedure, meaning patients usually go home the same day. Here’s what to expect:

• Preparation – A lightweight head frame may be attached to ensure precise targeting.
• Imaging –MRI or CT scans are performed to map the AVM accurately.
• Treatment planning –A team of neurosurgeons, radiation oncologists, and medical physicists creates a detailed plan to focus the radiation precisely.
• Radiation delivery –The patient lies comfortably in the Gamma Knife machine while dozens of radiation beams converge on the AVM. The process typically takes one to three hours, depending on the size and complexity of the AVM.

Because the beams are non-invasive, patients often experience little to no pain during the procedure, and sedation is usually minimal.

What are the benefits of Gamma Knife for AVMs?

Gamma Knife radiosurgery offers several advantages over traditional brain surgery:

• Non-invasive: No scalp incisions or open brain surgery.
• Precision:Healthy brain tissue surrounding the AVM is largely spared.
• Lower risk:Reduced risk of infection and surgical complications.
• Outpatient procedure: Most patients return home the same day.
• Gradual and effective: High success rates for small to medium AVMs, with many cases achieving full obliteration over time.

Are there risks or side effects?

Like any medical procedure, Gamma Knife treatment has potential side effects. Most patients experience mild headaches or nausea, which usually resolve quickly. Rarely, radiation can cause swelling or damage to nearby brain tissue, which is closely monitored during follow-up visits.

It’s important to remember that the full effect of the treatment takes months to years. During this time, patients should continue regular neurological monitoring and imaging to track progress and address any complications early.

How successful is Gamma Knife for AVMs?

Clinical studies show that Gamma Knife radiosurgery has high success rates, especially for smaller AVMs. For AVMs in critical or deep brain locations, Gamma Knife may be the safest and most effective option, offering patients improved quality of life with minimal disruption.

If you or a loved one has been diagnosed with an AVM, speaking with a specialist in radiosurgery can help determine whether Gamma Knife is the right treatment option. Awareness and understanding of this technology can empower patients to make informed decisions about their care and take a proactive approach to brain health.

Centres of Excellence for Stereotactic Radiosurgery treatment of complex Brain Tumours