It happens all the time on TV. A brain surgeon performs a risky surgery on a patient with a brain tumor that most will not operate on.
What if that approach wasn’t necessary – if you could stop a brain tumor from posing a threat without surgery? That treatment is possible with radiosurgery using the Gamma Knife.
How Gamma Knife works
Before treatment, someone from your care team places a frame with four pins on your head to restrict head movement. To map out the proper treatment, your team then performs an MRI to find the location of the tumor(s).
Once the team develops the treatment plan, the Gamma Knife uses 192 separate beams of radiation that meet at one point to make a supercharged dose of radiation. This kills the cancer cells at that location in your brain. The Gamma Knife then moves your head so it can target another location.
Where the beams come together, three different sizes can be used so the tumor is destroyed without affecting brain tissue.
“We can define volumes precisely enough to make sure we are hitting the tumor without including anything else within the 192-beam cluster,” said Dr. Warren Olds, a Marshfield Clinic radiation oncologist. “Whole-brain radiation at doses that would have any chances of affecting the cancer in your brain affects your memory and thinking.”
Gamma Knife is non-invasive, which means the process doesn’t include any cuts, anesthesia, bleeding, chance of infections, spinal fluid leaks, stroke, hair loss or any other problems that go along with other treatment options. It is also a relatively quick procedure. Some treatments last less than an hour, while more complex procedures may take several hours.
It is a way for our patients to get treatment for potentially very serious disorders with minimal risk, inconvenience and discomfort,” said Dr. John Neal, a Marshfield Clinic neurosurgeon. “For the most part, our patients are happy with the experience because they can walk in and walk out.”
Patients sometimes feel discomfort from the four pins that hold their head, and the frame can cause claustrophobia.
Brain tumors Gamma Knife can treat
While the Gamma Knife doesn’t treat all brain tumors, it can treat metastatic tumors, benign meningioma tumors and pituitary tumors. It also can treat other issues that are not cancer including acoustic neuromas, small vascular malformations and trigeminal neuralgia.
“For some of these conditions, like metastatic tumors, it is more effective than open surgery,” Neal said. “It has been a huge advance in how we can treat patients.”