First of all, a gamma knife isn’t a knife at all. It’s a form of radiation that’s used by surgeons to operate on brain tumors and other brain disorders. Gamma knife surgery, which is also called gamma knife radiosurgery, is usually a one time procedure that can be done in a day.
How Does It Work?
A gamma knife is an instrument that targets the tumor with miniscule beams of radiation. This technology is valuable because its effect on the healthy tissue the beams need to penetrate is minimal. Yet, the tumor or the other abnormality in the brain can still be treated with powerful radiation. This causes the cells in the tumor to die and if the cells die, they stop dividing and the tumor should shrink. A gamma knife also avoids the risks of cutting through the skull and the tissue that envelope the brain.
Why Is It Used?
Patients and surgeons opt for gamma knife radiosurgery when the brain tumor is located in a place where it’s too hard to reach by usual brain surgery. It’s also done when the patient isn’t well enough to withstand traditional brain surgery or if the patient doesn’t want invasive surgery.
Besides both malignant and benign brain tumors, gamma knife surgery is used to repair AVMs or arteriovenous malformations. This condition happens when the veins and arteries in the head hook up with each other directly. Normally, veins and arteries are connected through capillaries. AVMs are dangerous because they can lead to bleeding. Patients with AVMs also suffer from seizures ad headaches. The gamma knife radiotherapy causes the tangled veins and arteries to thicken and shut down.
Gamma knife surgery is also used to treat trigeminal neuralgia. The trigeminal nerves come from the brain and branch into the lower jaws, the cheeks and the forehead. When neuralgic develops in these nerves the patient can suffer debilitating pain. Gamma knife radiosurgery interrupts the signals from the nerves that cause the pain.
The gamma knife is also used to treat an acoustic neuroma, which is a benign tumor that presses on the nerve that controls a person’s sense of hearing and his or her balance. A gamma knife treatment can reduce this type of tumor without badly damaging the nerve. Gamma knife surgery can also be used to shrink tumors in the pituitary gland.
Because the gamma knife surgery doesn’t involve actually cutting into the skull, the risks of bleeding and infection can be avoided. The side effects of the surgery are usually temporary. The patient can suffer from fatigue, some swelling around the surgical site and a irritated or sensitive scalp where the gamma knife was focused.