ABOUT SRS (X-KNIFE)

Stereotactic radiosurgery is a highly precise form of radiation therapy used primarily to treat tumors and other abnormalities of the brain. Despite its name, stereotactic radiosurgery is a non-surgical procedure that uses highly focused x-rays to treat certain types of tumors, inoperable lesions and as a post-operative treatment to eliminate any leftover tumor tissue.

The treatment involves the delivery of a single high-dose-or sometimes smaller, multiple doses-of radiation beams that converge on the specific area of the brain where the tumor or other abnormality resides. Using a helmet-like device that keeps the head completely still and three-dimensional computer-aided planning software, stereotactic radiosurgery minimizes the amount of radiation to healthy brain tissue.

BRIEF ABOUT THE PROCEDURE

Stereotactic radiosurgery is an important alternative to invasive surgery, especially for tumors and blood vessel abnormalities located deep within or close to vital areas of the brain. Radiosurgery is used to treat many types of brain tumors, both benign or malignant and primary or metastic. Additionally, radiosurgery is used to treat arteriovenous malformations (AVMs), a tangle of expanded blood vessels that disrupts normal blood flow in the brain and is the leading cause of stroke in young people.

Although stereotactic radiosurgery is often completed in a one-day session, physicians sometimes recommend a fractionated treatment, in which treatments are given over a period of days or weeks. This is referred to as stereotactic radiotherapy.

Stereotactic radiosurgery works in the same way as other forms of radiation treatment. It does not actually remove the tumor; rather, it distorts the DNA of tumor cells. As a result, these cells lose their ability to reproduce. Following the treatment, benign tumors usually shrink over a period of 18 months to two years. Malignant and metastatic tumors may shrink more rapidly, even within a couple of months. When treated with radiosurgery, arteriovenous malformations (AVMs) begin to thicken and close off.