Now, fifteen years later, U.Va. neurosurgeons have treated nearly 5,000 patients from around the nation with the Gamma Knife for a variety of brain diseases without making a single large incision in the skull. U.Va. is also on its second Gamma Knife instrument.
"With experience comes a higher degree of technical success and fewer complications," said Dr Neal F. Kassell, professor of neurosurgery and one of three Gamma Knife experts at U.Va. "Patients know that when they come to U.Va. to have this type of surgery, they're getting the best possible chance of a cure."
The Gamma Knife, technically called stereotactic radiosurgery, allows surgeons to repair the brain without a scalpel, decreasing the pain, trauma and risks of open surgery such as hemorrhage, leaking cerebrospinal fluid and infection.
"The Gamma Knife uses 201 highly-focused beams of a radioactive isotope, Cobalt 60, to produce biological effects on brain tissue," explained Dr. Ladislau Steiner, director of the Lars Leksell Gamma Knife Center at U.Va. and a professor of neurosurgery and radiology. "The blades of the Gamma Knife are actually those beams of radiation specially programmed to target a lesion in the brain. This technique has revolutionized neurosurgery." Steiner helped Swedish inventor and physician Lars Leksell develop the Gamma Knife system in the 1950's and 60's and has 35 years of experience on the instrument.
Today, about thirty percent of Gamma Knife treatments at U.Va. are for cancer that has spread, or metastasized, to the brain. The overall success rates, according to data compiled by the department of neurosurgery, are encouraging.
"There is approximately a ninety percent success rate in terms of either shrinking a brain metastasis or halting its growth," said Dr. Jason P. Sheehan, associate director of the Gamma Knife Center and assistant professor of neurosurgery. "The Gamma Knife is a wonderful approach to treating patients who are not good candidates for open surgery or who have had previous surgeries. Also, if a tumor is small, less than three centimeters across for example, Gamma Knife surgery may actually be preferable over open surgical resection." The instrument may also be effective treatment for residual or recurrent lesions after conventional surgery.
Patients with malformed blood vessels in the brain, a condition called arteriovenous malformation (AVM) are also experiencing high success rates-- about eighty percent. Patients may also be potential candidates for the Gamma Knife if they have inner ear tumors (acoustic neuromas), pituitary tumors, epilepsy, movement disorders, pain from trigeminal neuralgia, obsessive-compulsive neurosis, dural malformations or uveal melanoma.
Most patients can tolerate the Gamma Knife if they can tolerate a simple surgical procedure. They can also be treated at any age- from as young as four to their 90's. Treatment lasts about one hour. Beforehand, a guiding device that resembles a halo is placed on the head while the patient is under local anesthesia in a U.Va. operating room. "From the moment patients arrive to the moment of discharge, the Gamma Knife experience at U.Va. is smoothly run," Sheehan said. "What we offer in terms of service that goes along with the purely technical side of the Gamma Knife is superb." For those considering Gamma Knife surgery, just visit http://www.