The Gamma Knife Radiosurgery is a form of stereotactic radiosurgery that uses computer-guided planning and radiation to treat primary and secondary brain tumours, vascular abnormalities, and other lesions in the brain. This radiosurgical approach has been applied by neurosurgeons around the world for more than five decades. Unlike conventional open brain surgery, such radiosurgery does not involve an incision or general anaesthesia; instead, it uses precise beams of gamma rays. Hence, the risks of bleeding, morbidity, and mortality are much lower as compared to open surgery.

With the help of three-dimensional computerised imaging, a highly concentrated dose of gamma radiation is delivered precisely to destroy the target cancerous cells or abnormal tissues. Through the destroying effect, the tumour generally shrinks in size over a period of months or years, and similarly lesions such as abnormal tangle of blood vessels will close off over time. The main benefit of Gamma Knife radiosurgery is its high degree of precision with minimal radiation injury to the surrounding healthy tissues, through the use of a stereotactic frame.

The Gamma Knife radiosurgery is typically performed on an outpatient basis, and less frequently an overnight hospital stay is required following the treatment. While some patients may experience mild and temporary tenderness or swelling around the frame fixation sites post-treatment, most patients would be able to return to their usual activities the following day.