Minimally Invasive Brain Surgery Gamma Knife® radiosurgery is a major advance that has changed the landscape within the field of neurosurgery. It has become a primary treatment for brain tumors, arteriovenous malformations, trigeminal neuralgia and other disorders. Gamma Knife makes it possible for patients to undergo a non-invasive form of brain surgery without trauma, surgical risks, a long hospital stay or subsequent rehabilitation. Gamma Knife is often the only treatment option for inoperable lesions and for patients who were formerly considered untreatable or at very high risk for open skull surgery.
Gamma Knife radiosurgery is a minimally invasive technique that is an alternative to conventional neurosurgery for many indications. Diseased tissue is treated with a single precisely-focused destructive dose of gamma rays. Normal brain tissue adjacent to the diseased tissue receives little radiation. Gamma Knife is a revolutionary breakthrough in brain surgery technology that includes these advantages:
- Superior outcomes documented by 20 years of studies and peer-reviewed medical journals
- Designed specifically to treat brain disorders providing greater accuracy than other radiosurgery systems
- Delivers significantly lower dose of radiation to surrounding healthy tissue than CyberKnife, linear accelerator, or fractionated radiation therapy
- Utilizes stereotactic frame technology that defines the standard for radiosurgery accuracy (especially vital for small tumors near sensitive neural structures)
- Imaging, planning and treatment performed on the same day, as an outpatient procedure
- Higher rates of patient satisfaction than microsurgery
- No incisions or general anesthesia
- No risk of intracranial bleeding or infection
- Low risk of post-surgical complications
- Rapid return to normal activities
- No hair loss or scarring
- Long term control of tumors and other disease
- Indicated by the FDA for the treatment of brain metastases
- Considered the “Gold Standard” of radiosurgery
The Gamma Knife is not a knife at all, but a medical instrument that emits 192 finely focused beams of gamma radiation. These beams simultaneously intersect at the precise location of the brain disorder and treat it with minimal effect on surrounding normal tissue and without the usual risks of surgery or an incision.
Gamma Knife surgery maximizes patient comfort and can be used to treat lesions that before were either inaccessible or were treated unsuccessfully by conventional surgery, chemotherapy and/or radiation therapy. Safe and Effective Gamma Knife surgery is unique because no surgical incision is performed to “expose” the lesion. Patients routinely receive only a mild sedative, thus eliminating the side effects and dangers of general anesthesia.
The success rate of the Gamma Knife is unprecedented. More than 400,000 patients have had Gamma Knife surgery with no mortality, and minimal morbidity reported. Backed by two decades of pre-clinical research, no other neurosurgical tool has met with such impressive results. Clinical applications continue to grow, and its many benefits as a minimally invasive procedure continue to make it the treatment of choice. Treatment Protocol A patient accepted for treatment generally arrives at the Gamma Knife Center and is admitted the morning of the procedure. A lightweight head frame is used as the most accurate system to target the lesion; and, is applied under local anesthetic with four pins. With the frame in place, the patient receives an MRI or CT imaging study, or angiography in the case of arteriovenous malformation, to precisely locate the diseased area to be treated.
Data from the imaging study is transferred to the Gamma Knife computer system. While the patient rests, the Gamma Knife Center team uses advanced software to determine the treatment plan. This takes one or two hours to complete depending on the complexity and location of the diseased area.
When the individualized treatment plan is completed, the patient is placed on the Gamma Knife couch and is comfortably positioned. The patient is then moved automatically head first into the Gamma Knife and treatment begins. Treatment typically lasts from 15 minutes to an hour, during which time the patient feels nothing unusual. At the completion of the treatment the patient is automatically moved out of the Gamma Knife, and the head frame is removed. Patients are usually able to leave the treatment center the same day and resume their normal activities. The patient’s physician will arrange periodic follow-up examinations and brain imaging to follow the effects of treatment.
The results of Gamma Knife radiosurgery appear over days, weeks or months, depending on the type of lesion being treated. Most lesions dissolve or sclerose gradually, eventually disappearing. Others simply exhibit no further growth. Patient Selection Selection of patients for Gamma Knife surgery involves a multidisciplinary team of neurosurgeons, radiation oncologists and other specialists. Selection is made on the basis of a diagnostic examination, imaging studies, tissue diagnosis and the patient’s general health and age. Patients may be eligible for Gamma Knife treatment even if they previously had open brain surgery, radiation therapy, chemotherapy, or in the case of AVMs, embolization procedures. In general, tumors and arteriovenous malformations should be less than 4 cm. in diameter. Patient Benefits Conventional neurosurgery means a lengthy post-surgical hospital stay, expensive medication and sometimes months of rehabilitation. The Gamma Knife greatly reduces these costs. Patients are usually able to leave the treatment center the same day and resume their normal activities. Post-surgical disability and convalescent costs are non-existent.