Some people are not able to undergo deep brain stimulation surgery to alleviate their Parkinson's disease tremors. For example, some people taking anticoagulant drugs (blood thinners) cannot go without their medicine even for a short period of time. For these people, a non-invasive surgical approach, like gamma knife surgery, may be beneficial. While gamma knife is not as effective as deep brain stimulation, it does offer another treatment option for some.
What Is Gamma Knife?
Not actually a "knife" at all, the gamma knife is a machine that emits hundreds of powerful, highly focused gamma radiation beams. The gamma knife allows for a more precise and concentrated treatment than do other radiation treatment options. This helps the doctors target the diseased area of the brain while sparing the healthy areas surrounding it.
How Does Gamma Knife Work?
A multidisciplinary team of neurosurgeons, neuroradiologists, radiation oncologists, radiation physicists, and specialized nurses works closely together to ensure precise and effective treatment with the gamma knife.
First, the patient is fitted with a head frame, and the target within the brain is pinpointed using specialized imaging scans, such as magnetic resonance imaging (MRI) or computed tomography (CT). The frame is positioned in a special helmet so the radiation will be directed at the targeted area. The patient lies on a bed that slides into the gamma knife machine. Radiation is delivered through 201 ports inside the helmet, with the beams intersecting at the target.
The procedure takes 15 to 40 minutes and typically is performed with local anesthesia (pain-relieving medication). During treatment, a video system and two-way intercom allow the patient and doctors to remain in contact.
Patients undergoing gamma knife treatment experience minimal, if any, discomfort and serious side effects are rare. Gamma knife treatment is usually performed on an outpatient basis.
When Is Gamma Knife Treatment Used for Parkinson's Disease?
Gamma knife treatment is considered only when a person is not able to get relief from medication and when deep brain stimulation, which is a more effective therapy for Parkinson's disease, is not appropriate.
There are many important issues to be addressed when considering gamma knife treatment. These issues should be discussed with a movement disorders expert or a specially trained neurologist and further discussed with the radiation oncology experts that actually do the procedure.
How Successful Is Gamma Knife Treatment?
The benefits of gamma knife treatment occur over time, usually several months to several years, depending on the person's medical condition.
Gamma knife treatment for Parkinson's disease has up to a 70%-90% success rate, which depends on the patient and the severity of the disease.
Are There Risks Associated With the Procedure?
As with all surgical procedures, there is a small risk of complications. Be sure to talk to your doctor about these risks when considering gamma knife treatment for Parkinson's disease.