Stereotactic Radiosurgery (SRS)
Stereotactic radiosurgery (SRS) uses many precisely focused radiation beams to treat tumors and other problems in the brain, neck and other parts of the body.
It is not surgery in the traditional sense because there's no incision. Instead, SRS uses 3-D imaging to target high doses of radiation to the affected area with minimal impact on the surrounding healthy tissue.
Like other forms of radiation, stereotactic radiosurgery works by damaging the DNA of the targeted cells. The affected cells then lose the ability to reproduce, which causes tumors to shrink.
Stereotactic radiosurgery of the brain and spine is typically completed in a single session. Body radiosurgery is used to treat lung, liver, adrenal and other soft tissue tumors, and treatment typically involves multiple sessions.
When doctors use stereotactic radiosurgery to treat tumors in areas of the body other than the brain, it's sometimes called stereotactic body radiotherapy (SRBT) or stereotactic ablative radiotherapy (SABR).
Stereotactic radiosurgery doesn't involve surgical incisions, so it's generally less risky than traditional surgery. In traditional surgery, you may have risks of complications with anesthesia, bleeding and infection.
Early complications or side effects are usually temporary. They may include:
- Fatigue. Tiredness and fatigue may occur for the first few weeks after SRS.
- Swelling. Swelling in the brain at or near the treatment site can cause signs and symptoms such as headache, nausea and vomiting. Your doctor may prescribe anti-inflammatory medications (corticosteroid medications) to prevent such problems or to treat symptoms if they appear.
- Scalp and hair problems. Your scalp may be red, irritated or sensitive at sites where a device is attached to your head during the treatment. Some people temporarily lose a small amount of hair.
Why it's done
- Brain tumor. Radiosurgery, such as Gamma Knife, is often used to treat noncancerous (benign) and cancerous (malignant) brain tumors, including meningioma, glioma, anaplastic astrocytoma, glioblastoma, chordoma, chondrosarcoma, hemangioblastoma and craniopharyngioma. SRS may also be used to treat cancers that have spread to the brain from other parts of the body.
- Arteriovenous malformation (AVM). AVMs are abnormal tangles of arteries and veins in your brain. In an AVM, blood flows directly from your arteries to veins, bypassing smaller blood vessels (capillaries). AVMs may disrupt the normal flow of blood and lead to bleeding (hemorrhage) or stroke.Stereotactic radiosurgery destroys the AVM and causes the affected blood vessels to close off over time.
- Trigeminal neuralgia. Trigeminal neuralgia is a chronic pain disorder of one or both of the trigeminal nerves, which relay sensory information between your brain and areas of your forehead, cheek and lower jaw. This nerve disorder causes extreme facial pain that feels like an electric shock.SRS treatment for trigeminal neuralgia targets the nerve root to disrupt these pain signals.
- Acoustic neuroma. An acoustic neuroma (vestibular schwannoma), is a noncancerous tumor that develops along the main balance and hearing nerve leading from your inner ear to your brain.When the tumor puts pressure on the nerve, a person can experience hearing loss, dizziness, loss of balance and ringing in the ear (tinnitus). As the tumor grows, it can also put pressure on the nerves affecting sensations and muscle movement in the face.Stereotactic radiosurgery may stop the growth or minimize the size of an acoustic neuroma with little risk of permanent nerve damage.
- Pituitary tumors. Tumors of the bean-sized gland at the base of the brain (pituitary gland) can cause a variety of problems. The pituitary gland controls hormones in your body that control various functions, such as your stress response, metabolism, growth and sexual function.Radiosurgery can be used to shrink the tumor and lessen the disruption of pituitary hormone regulation.
- Tremors. Stereotactic radiosurgery may be used to treat tremors associated with functional neurological disorders such as Parkinson's disease and essential tremor.
- Other cancers. SRS may be used to treat cancers of the liver, lung and spine.