Radiosurgery: An Introduction

Brain surgery can be a daunting prospect and traditional neurosurgery is often painful and requires a lengthy recovery time. Even so, the patient may not be completely rid of the tumor and recurrence can always occur. An alternative to traditional brain surgery is stereotactic radiosurgery, which utilizes beams of radiation to target a brain tumor in a completely non-invasive way.

The first step in radiosurgery is a CT-scan. These scans of the brain reveal the exact size and location of the tumor within the brain. These scans also calculate the hounsfield unit, which is the density of different tissues. These units help doctors determine how the radiation will travel through the brain. In cases where the tumor is in softer tissue, an additional MRI may be ordered to get a finer and more accurate picture of the tumor.

Radiosurgery is dependent on different beams of radiation. Alone, each beam has a low dose of radiation, but together the rays produce enough power to destroy tumors. There are two main advantages to using multiple low-dosage beams instead of fewer high-dosage beams. The first is that the use of multiple beams leaves the surrounding tissue relatively unharmed, meaning that there is minimal impact on the healthy cells in the brain. The other advantage is that the usage of multiple beams allows doctors to find the best angles and routes as well as adjust individual beam intensity to get rid of the tumor as thoroughly as possible.