Radiosurgery Technology

Radiosurgery technology has advanced significantly since the 1950s when it was developed to treat only brain tumors. Baylor features two advanced machines to treat a variety of tumors and conditions throughout the body: Gamma Knife and CyberKnife

Gamma Knife Technology

The Gamma Knife is not a knife at all but a 22-ton metal sphere about six feet in diameter, that holds 201 separate pieces of radioactive cobalt. Inserted through an opening in the side of this sphere is a 500-pound metal helmet shaped like a hollow cylinder and perforated by 201 holes.

During treatment, the patients head is positioned within the helmet so the tumor is at the helmets center and radiation flows through each of the holes to the center point. This is how the center point receives 201 doses one for each hole while points nearby receive a does only from a single hole.

A tumor with a complex shape can be treated by repeating this process several times, shifting the head slightly within the helmet each time to treat a different area. With the aid of sophisticated software, radiation can be focused on almost any shape with high precision.

CyberKnife Technology

The CyberKnife is a sophisticated radiosurgery system that blends robotics, imaging and radiotherapy technology to deliver precise doses of radiation anywhere in the body. It consists of a large robot about nine feet tall that moves a linear accelerator around the patient to deliver beams of radiation one at a time.

During treatment, the system uses X-rays taken of the patient to tell the robot how to compensate for any patient movement. Because the robot then tracks the patient with this technique, a head frame is not required to maintain precision and the tumor targets are not limited to the brain. The CyberKnife can reach any organ in the body.

The ability of the CyberKnife to treat without a head frame gives it significant advantages. First, tumors in any organ of the body can be treated and second, radiosurgery can be offered to infants and young children with fragile skulls who are not suitable for a rigid head frame. Finally, radiosurgical treatments can be delivered over several days instead of all at once which may add safety in some cases.