Gamma Knife Radiosurgery Brain Surgery Without an Incision The Gamma Knife is an advanced tool for the treatment of benign and malignant tumors, arteriovenous malformations (AVMs), facial pain, and other functional brain disorders. It is not actually a knife, but a 20-ton medical instrument that emits 201 finely focused beams of gamma radiation. These beams simultaneously intersect at the precise location of the brain disorder and treat it with minimal effect on surrounding normal tissue – without the risks of surgery or an incision. WVU's Gamma Knife has greatly increased our ability to provide the full range of advanced neurosurgical care to patients. Gamma Knife radiosurgery maximizes patient comfort and can treat lesions that were previously inaccessible or treated unsuccessfully by conventional surgery, chemotherapy, or radiation therapy.