All About the Gamma Knife

In 1949, Prof. Lars Leksell of the Karolinska Institute in Sweden discovered that by miniaturizing surgical intervention in the skull, thus reducing the mortality rate and the trauma to the patient. Leksell's stereotactic frame, and the concept of using beams of X-rays to surgically treat lesions in the brain, led to the creation of the Gamma Knife. The first commercial version of the system was introduced in 1986, with nearly 7,000 patients undergoing surgery with it over the next five years. By 2006, that number had increased to nearly half a million.

The Gamma Knife uses ionizing gamma radiation emitted from 192 cobalt-60 radioactive sources whose beams converge on a precise selected area of the brain. Highly sophisticated computer software is used to determine the size, location and shape of the area to be treated. Only at the point where all 192 beams cross is enough radiation delivered to affect the diseased tissue. Because only the tissue being treated receives a significant radiation dose, there is minimal effect on the surrounding healthy tissue.

No incisions need to be made to expose the brain, thereby reducing the risk of surgical complications - such as infection and hemorrhages - and eliminating the side effects and dangers of general anesthesia. The treatment is done on an outpatient basis, with an overnight hospital stay required in some cases. Patients can resume their previous activities almost immediately. Gamma Knife radiosurgery is much safer than traditional brain surgery, with a much lower complication rate.

Gamma Knife radiosurgery, which has been used at UAMS since 1999, is a simple procedure. The new Gamma Knife Perfexion system, launched in 2006, has the distinct advantage of delivering a significantly reduced amount of radiation during treatment to non-targeted areas, 100 times less compared to competing systems, making it safer for patients who may not have been considered for such treatment, such as children and women of childbearing age.