Another highly specialized type of external beam radiation is stereotactic radiosurgery (SRS).  Small brain tumors and arteriovenous abnormalities (AVMs) can be treated using this technique that delivers multiple pinpoint doses of high energy radiation to a targeted abnormality.

SRS procedure is a team effort. The procedure involves the concentrated effort of the radiation oncologist, neurologist and medical radiation physicist. The procedure is completed in one day, though the actual treatment time typically takes less than 30 minutes.

The Procedure

On the day of treatment, the neurosurgeon attaches the head frame to the patient.  The head frame remains on the patient for the entire procedure: it provides a reference platform fro the location of the patient’s anatomy and tumor during imaging.  It also serves to immobilize the patient during treatment.  After the frame is in place, a series of CT and/or MRI scans are taken.

After the scan is taken, the patient simply rests while the imaging data is transferred to a specialized computer system.  In many cases the patient can read, watch television or even eat while planning takes place.

The computer system determines the precise target position, dosage and configuration of radiation beams.  This positioning optimizes the dose to the tumor, while minimizing the exposure of healthy tissue.   Once the treatment plan is approved by the radiation oncologist, the linear accelerator undergoes a series of quality assurance checks, and then treatment can begin.