In stereotactic radiosurgery (SRS), three-dimensional coordination systems (stereotaxy) are coordinated with the patient’s diagnostic images. High-dose single fraction radiation is then delivered to the target in the brain in sharp and accurate borders. This procedure can also be applied outside the central nervous system.

Gamma knife is specifically used to treat brain tumors by “concentrating high-intensity Gamma radiation into a small volume”. In Gamma Knife treatment, many gamma radiation rays are accurately focused on the tumor and all the rays are concentrated in the tumor volume. Because the intensity of each individual ray is relatively low, the radiation has just a minor harmful effect on the normal brain tissue surrounding the tumor. So, while Gamma Knife treatment kills cancer cells and shrinks tumors, it does not damage healthy surrounding tissue because it concentrates the radiation precisely within the tumor boundaries.

Gamma Knife radiosurgery is known to be effective for benign or malignant brain tumors up to 4 centimeters in size (such as acoustic neuromas, germinomas, meningiomas, metastases), vascular malformations such as arteriovenous malformations (AVM), pain and other functional problems such as trigeminal neuralgia. Radiosurgery usually does not completely remove the tumor. Biologically inactivating the tumor and stopping lesion growth is considered “treatment success”. Acute complications following Gamma Knife radiosurgery are rare.