Gamma Knife Frequently Asked Questions

The Gamma Knife® Icon™, a non-invasive, state-of-the-art, stereotactic radiosurgical tool, is an alternative or supplemental treatment to traditional brain surgery. Gamma Knife is used to precisely target malignant and benign brain tumors and disorders by using finely-focused radiation beams that minimize damage to your healthy brain tissue. The procedure is typically performed in an outpatient treatment session with considerably reduced treatment times and minimized surgical complications.

Gamma Knife utilizes the latest advanced diagnostic imaging and 3D treatment planning software to deliver finely focused beams of gamma radiation to small targets inside your brain. The beams converge at a point to treat the affected tissue, while minimizing the damage to healthy brain tissue.

Gamma Knife treatment has many benefits: 

• It is bloodless.
• It is virtually painless.
• There is no loss of hair.
• It allows rapid return to pre-treatment activities.
• Gamma Knife treatment may be suggested as an adjunct to standard neurosurgical therapy or as the preferred course of treatment when further traditional therapy is not recommended.
• Gamma Knife treatment may also replace brain surgery in some patients with brain tumors, vascular malformations, and facial pain. 
• If you would be at risk for complications from conventional surgery, you may be a candidate for Gamma Knife radiosurgery. 
• Gamma Knife treatment can be used when prior surgery or radiation therapy has failed to control the disease process. 
• It can also be used in conjunction with conventional surgery in previously inoperable cases, other forms of radiation therapy, and chemotherapy.
• In contrast to conventional radiation therapy of the brain, Gamma Knife treatment is only directed to targeted areas and spares unnecessary treatment of adjacent, normal brain tissue. 
• Treatment can often be done in only a single session, although the equipment accommodates multiple sessions, enabling treatment of larger tumor volumes, and targets close to critical brain structures and new or recurring brain metastases.

If you are of advanced age or in poor medical condition, you may be at an unacceptably high risk for anesthesia and conventional surgery, making Gamma Knife treatment an ideal solution. Gamma Knife radiosurgery is also especially valuable if you have a neurological disorder that would require a difficult surgical approach or may be impossible to treat using conventional neurosurgical techniques. 

Gamma Knife treatment also is highly beneficial if your lesions are situated in an inaccessible or functionally critical area within the brain. In addition, the treatment can be used as an adjunct to your care if you have already undergone conventional brain surgery, interventional neuroradiology, conventional radiation therapy, or chemotherapy.

Some of the conditions that can be treated with this technology include: 

• Malignant Tumors: metastatic tumors (cancer spread to the brain), gliomas, chondrosarcoma
• Benign Tumors: acoustic neuromas (vestibular schwannomas), meningiomas, pituitary adenomas, low-grade gliomas, and skull-based tumors
• Vascular Abnormalities: arteriovenous malformations (AVMs), cavernous angiomas (cavernous malformations)
• Functional Disorders: trigeminal neuralgia (also known as tic douloureux or chronic facial pain)

You may be a candidate for Gamma Knife if you: 

• Have a brain tumor
• Have a vascular disorder
• Are not a candidate for conventional neurosurgery or radiation therapy
• Need additional therapy after you have already undergone surgery, chemotherapy, or radiation

Gamma Knife may also be recommended for you if you have:

• Tumors or vascular malformations that are surgically inaccessible
• Risk factors that make surgery inadvisable
• Need for an additional dose of radiation following radiation therapy
• Recurrent tumors
• Facial Pain

Most patients are referred to the Fort Sanders Regional Gamma Knife Center at Thompson Cancer Survival Center by their doctors. However, you can make a self-referral. The Gamma Knife team will review your records to determine if Gamma Knife treatment is appropriate.

• Your medical and surgical history
• Clinical examinations
• Imaging studies, such as MRI, CT and/or PET scans

The Gamma Knife’s success rate is impressive. Supported by more than three decades of clinical research, this neurosurgical tool has yielded unprecedented results. Clinical applications continue to grow, and its many benefits as a non-invasive treatment modality continue to make it the treatment of choice for certain clinical conditions. This does not include research indications.

You will remain conscious throughout the entire procedure and may communicate with the treatment team through a two-way microphone. The team will monitor you during treatment by video and sound.

No, your head will not be shaved. In rare cases, the treatment may cause some hair loss.

The effects of Gamma Knife radiosurgery occur over several days to several years, depending on the type of medical condition treated. The radiation alters the DNA of the tumor or lesion being treated so that the cells no longer reproduce, eventually rendering the lesion static. Some abnormalities dissolve gradually, eventually disappearing. Others simply exhibit no further growth. 

The effectiveness of your treatment will be monitored by MRI scans at regular intervals. The goal of radiosurgery is tumor control, which is defined as stable tumor size or tumor shrinkage. For vascular malformations, control is generally considered total obliteration.

Possible Early Complications

Some common side effects you may experience are: 

• Local pain and swelling in the scalp
• Headache

Rare complications can include:

• Skin reddening and irritation
• Nausea
• Seizure

Possible Delayed Complications

Uncommon complications you could experience include:

• Local loss of hair in superficial lesions
• Local brain swelling at the treatment site
• Local tissue necrosis in the treatment site

Rare Complications

• Vision loss (dependent on diagnosis and areas treated)
• Hearing loss (dependent on diagnosis and areas treated)

You will most likely be able to return to pre-treatment activities within a few days. The only restrictions you will have are the same ones you had prior to your treatment.

Cost studies have shown Gamma Knife radiosurgery to be less expensive than conventional neurosurgery because it eliminates: 

• Lengthy post-surgical hospital stays
• Expensive medication
• Potentially months of rehabilitation

Perhaps the most important factor which will reduce your cost is that there are virtually no post-surgical disability costs with this procedure.

Most likely, yes. Fortunately, Gamma Knife radiosurgery is reimbursed by most insurance companies, PPOs, HMOs, and Medicare.