Gamma Knife Surgery

Gamma Knife surgery, also referred as stereotactic radiosurgery, is a highly advanced non-invasive neurosurgical procedure for treating various brain conditions and tumors. The gamma knife surgery does not involve anything related with a knife, but actually employs radiation for treatment. Gamma knife contains radiation sources that are placed in a circular set in a heavily shielded unit. The unit directs precise gamma radiation to the selected target area in the brain. These beams are very safe and do not affect the functioning of the brain tissues through which they pass and that of the surrounding tissues. The radiation produces the required result only at the site where all beams meet.


Gamma-knife surgery is an appropriate alternative to standard invasive brain surgery (neurosurgery). It has the advantage that it can be performed in areas where standard neurosurgery is difficult to perform. Beside this, it is also suitable for unhealthy patients or patients who do not want to undergo invasive procedures. Gamma-knife surgery is widely recommended for the following conditions:

  • Brain tumor
  • Arteriovenous malformation (AVM)
  • Trigeminal neuralgia
  • Acoustic neuroma
  • Pituitary tumors


Gamma-knife surgery is usually performed on an outpatient basis. Patients should bring someone to stay with them and also to drive them back home. In some cases, an overnight stay of the patient undergoing surgery may be needed.

Before the procedure, a lightweight frame is fixed to the head of the patient with four pins. This frame stabilizes the head during the procedure and acts as reference point for the beams of radiation. After that, the patient undergoes imaging scans of the brain to locate the tumors and other irregularities. Then the results of the brain scans are entered into the computerized system to configure the optimal dose and placement of radiation beams.

During the procedure the patient is laid on a bed that slides into the gamma-knife machine. The head frame of the patient is firmly attached to a specialized helmet present inside the machine. The duration of the radiation treatment depends upon the shape and size of the target and may range from 1-4 hours. During the procedure the patient can talk with the doctor through a microphone.

After the procedure is complete, the head frame is removed. This may result in some minor bleeding at the pin sites. Patients may feel headache, nausea, or vomiting just after the procedure that can be treated with appropriate medications.

Risks and complications

Gamma-knife radiosurgery possesses less risks and complications as compared to traditional neurosurgery, as it doesn’t involve surgical incisions. Gamma-knife surgery may show some early complications that may disappear with time that include:

  • Tiredness and fatigue, in the first few weeks
  • Swelling in brain area can cause headache, nausea and vomiting
  • Rashes or redness on the scalp
  • Rarely, hair loss