What is Stereotactic Radiosurgery?
Stereotactic radiosurgery, also known as stereotactic radiotherapy (SRT),
is a minimally invasive treatment for many tumors, abnormalities and functional
disorders of the brain, head or upper neck. Although called radiosurgery,
the procedure does not require a surgical incision. We call it surgery
because stereotactic radiosurgery can have the same precision and result
as open surgery, but with the advantages of a minimally invasive procedure.
With minimally invasive stereotactic radiosurgery, it is not necessary
to open the skull to treat tumors or lesions in the brain. Stereotactic
radiosurgery is also a good alternative to whole brain radiation therapy,
as radiation exposure is limited to the treatment site while other areas
of the head and neck are not affected.
In performing stereotactic radiosurgery, physicians use sophisticated technology
to direct powerful, beams of ionizing radiation to the tumor or abnormality.
Because the radiation is so precisely focused, nearby healthy tissues
and other structures are unharmed. Since no incision is required, the
procedure is virtually painless. Patients return home the same day and
can resume normal activities right away.
The three types of stereotactic radiosurgery are:
- cobalt-60 based (photon)
- particle beam (proton)
- linear accelerator-based (linac)
What conditions are treated with stereotactic radiosurgery?
Stereotactic radiosurgery can treat:
- metastatic brain tumors (tumors originally arising outside of the brain,
such as lung cancer or breast cancer)
- benign (non-cancerous) brain tumors, such as acoustic neuromas, meningiomas
and pituitary tumors
- malignant (cancerous) brain tumors
- arteriovenous malformations (a disorder of the blood vessels)
- trigeminal neuraligia
- certain seizure disorders
Stereotactic radiosurgery is an excellent option for patients who are not
good candidates for traditional open surgery, including patients whose
tumor or lesion is:
- inaccessible through open surgery
- located very close to arteries, nerves and other important structures in
the head and neck
How does stereotactic radiosurgery work?
As with other forms of radiation treatment, stereotactic radiosurgery does
not remove the tumor or lesion. Rather, the radiation breaks the DNA in
tumor cells so they are unable to reproduce. As a result, the targeted
lesion is converted to dead scar tissue and often becomes smaller over time.
With stereotactic radiosurgery, trained neurosurgeons, radiation oncologists
and other experts use 3-D computer-aided planning to map out the procedure
according to each patient's condition. Based on the computer mapping,
they apply complex technology to very accurately deliver radiation to
the treatment site.
Shrinkage of the tumor or lesion can take anywhere from a few months to
a few years, depending on the normal growth rate of the abnormality. Fast-growing
lesions, like malignant or metastatic tumors, tend to shrink more quickly
than benign tumors and blood vessel defects.