Gamma Knife Side Effects: Seizures

Has your doctor recommended Gamma Knife radiosurgery to treat your medical condition? Educating yourself about the procedure is a great way to play an active role in your care. One aspect that’s particularly important to understand is what to expect after treatment. This can help you prepare for any side effects that you may experience during your recovery, giving you an idea of what could occur and how to manage any discomfort.

The information below will help you better understand the Gamma Knife technology and what conditions it may treat. It also explains some Gamma Knife side effects that can occur after treatment, with a special discussion regarding seizures. This can help form the basis of your next conversation with your doctor, who can help resolve any lingering questions you may have.

What is Gamma Knife Radiosurgery?

It may sound like surgical treatment, but Gamma Knife radiosurgery is actually a minimally invasive procedure that uses radiation to treat conditions of the brain, head and neck. There are no incisions, no scalpels and no scars. There’s not even a hospital stay. The actual procedure only takes from 15 minutes to a little over an hour, and most patients are back to normal activities – including work – within a day or two.

The Gamma Knife system uses 192 individual beams of high-dose radiation to treat an area as small as 0.15 mm. That’s less than the width of a single human hair. These individual beams combine to have a therapeutic effect but spare healthy neighboring tissues. This results in fewer unpleasant side effects than traditional therapy, all without the risks related to surgery.

What Are Side Effects of Gamma Knife Radiosurgery?

While there are specific side effects you may experience due to your specific condition, there are some that are related to Gamma Knife radiosurgery itself. Understanding these beforehand can help you in your discussions with your doctor as you prepare for your recovery process. Some possible side effects occur right after treatment, and others may happen on a delayed basis.

Immediate possible side effects include:

  • Headache – The most common side effect, typically mild to moderate in severity. Headaches may start immediately after treatment but usually only last a day or two. Over-the-counter medications can help manage discomfort, and discussing your options with your doctor beforehand can help you be prepared for any headaches that do occur.
  • Nausea – Rarely, some patients experience nausea after treatment. This also only lasts a day or two and is typically mild. Again, you can discuss how to manage nausea with your doctor before treatment so you can deal with any discomfort, should it occur.
  • Scalp discomfort – Sometimes the areas where the headframe attaches become red, itchy or painful. Sometimes the treatment area can become red and itchy, as well. If this occurs, let your doctor know and he or she can help you be more comfortable.

A potential delayed effect is swelling of the brain at the treatment site. Your doctor will monitor you at your follow-up visits for any signs or symptoms of swelling. Should it occur, your doctor will prescribe medication to resolve the condition.

Gamma Knife Side Effects: Seizures

You may have come across seizures listed as a possible side effect of Gamma Knife radiosurgery. There have been cases where seizures have occurred in patients after treatment, but it’s important to understand that these patients typically have had some sort of seizure-related condition beforehand. This could include epilepsy, arteriovenous malformation or brain tumors.

Interestingly, studies have shown promise with using Gamma Knife radiosurgery to treat some seizure conditions, such as mesial temporal lobe epilepsy. However, side effects for treating this condition include a transient increase in seizures. If you have concerns about whether you are at risk for seizures following Gamma Knife radiosurgery, be sure to speak to your doctor about your risk.

What Conditions Can Be Treated with Gamma Knife Radiosurgery?

Gamma Knife is a form of stereotactic radiosurgery, and it was developed specifically for treating brain, head and neck conditions. Sometimes it is used alone, but it can also be used in conjunction with other therapies. One common use is following surgical removal of a brain tumor to eliminate any lingering cells. 

Some conditions commonly treated with Gamma Knife radiosurgery include:


Many patients can benefit from Gamma Knife radiosurgery as part of their treatment plan. To date, over 1 million patients have been treated worldwide. While it will be up to your doctor to determine if you are a good candidate for Gamma Knife radiosurgery, patients who may benefit from the procedure include people who cannot undergo surgery due to increased risks, people who have not responded to other treatments and people who simply prefer a minimally invasive option.

Continue Educating Yourself

Many patients find taking the extra time to learn about their condition and treatment options truly pays off in the form of confidence and peace of mind. Self-education is a powerful thing, and you’ve already taken steps to become a more informed patient. Continue the learning process, wherever you are along your treatment path. It will help you rest easy knowing you’ve made the right choices and your health is in good hands.

Anthony D’Ambrosio, M.D., M.B.A., F.A.A.N.S
Anthony D’Ambrosio, M.D., M.B.A., F.A.A.N.S
Dr. Anthony D’Ambrosio is a board-certified neurosurgeon that specializes in Neurosurgery, Stereotactic Radiosurgery, Gamma Knife Radiosurgery (GKRS) and more. He is the Director of Neurosurgery and Co-Director of the Gamma Knife Program at The Valley Hospital. Dr. D’Ambrosio is an expert in treating patients with trigeminal neuralgia, benign or malignant brain tumors, as well as many other neurological conditions.

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