What is a Gamma Knife?

The Gamma Knife is one of the most important medical achievements in the fight against diseases that are difficult to treat, especially certain forms of cancer. While not actually a knife, this stereotactic radiosurgical device provides a non-invasive method to approach various conditions, offering important out-patient treatments.

How It Works

The Gamma Knife works by employing a form of radiation known as gamma radiation. Instead of exposing the entire treatment area to radiation, the Gamma Knife is capable of delivering gamma radiation directly to small treatment areas. This precision is especially important for treating brain cancers, as the radiation can be delivered to the tumor site to destroy the DNA of the cancer cells with less risk of destroying surrounding tissues. Unlike other treatment methods like brain surgery, the Gamma Knife is non-invasive. This benefit removes risks associated with anesthesia and the potential for hemorrhage or infections from more invasive procedures.

What it Treats

The primary use for Gamma Knife procedures are cancers, especially malignant brain cancers as well as benign brain tumors like meningiomas. Other uses include treatments for vascular malformations like cavernous angiomas and arteriovenous malformations, acoustic neuroma and trigeminal neuralgia. Research is also progressing towards uses for chronic pain, epilepsy and Parkinson’s disease.


Like any medical procedure there are potential safety issues and complications. Common side effects include swelling, pain, headaches and nausea. More serious but less common risks may include swelling of the brain, seizures and vision or hearing loss. Risks vary depending on what area of the brain is treated.

While complications may occur, the benefits more than outweigh the risks, especially considering alternative treatment methods like invasive brain surgery. As technology continues to advance and improve, procedures like the gamma knife will only get better and more accurate, providing a hopeful future for patients throughout the world.