What is Gamma Knife Radiosurgery?
Gamma knife radiosurgery is a special non-operative procedure that uses focused beam gamma radiation directed towards your head to treat brain abnormalities such as vascular malformations (defects in the blood vessels supplying the brain) and tumors such as meningiomas.
Gamma knife radiosurgery works by distorting and destroying the DNA of the lesions/tumors in the brain, which results in these cells losing their ability to reproduce and die.
For gamma knife radiosurgery, your neurosurgeon uses specialized computer technology and imaging tests to locate and precisely deliver a concentrated dose of radiation to brain tumors or lesions in a single session with minimal impact on the surrounding healthy tissue.
Some of the key features of gamma knife radiosurgery include:
- Does not require any incisions
- Relatively safe
- General anesthesia is not needed for adults
What are the Indications for Gamma Knife Radiosurgery?
Gamma knife radiosurgery is typically recommended for small tumors with a diameter of 4 cm or less. The common indications for gamma knife radiosurgery include:
- Meningioma: Brain tumor
- Malignant glioma: A type of tumor that occurs in the brain and spinal cord
- Nerve conditions that are hard to reach or too risky to treat in other ways
- Trigeminal neuralgia: A disorder of the trigeminal nerve leading to facial pain
- Arteriovenous malformation (AVM): The arteries and veins are tangled
- Metastasis of cancer to the head, brain, or neck area
- If the patient is sensitive or not a suitable candidate for open or minimally invasive surgery
- Certain other health complications
Preparation for Gamma Knife Radiosurgery
Preparation for gamma knife radiosurgery includes:
- A thorough physical examination by your doctor is done to check for any medical issues that need to be addressed prior to radiosurgery.
- Blood and imaging tests such as X-rays, CT scans, or MRI are ordered to determine brain abnormality and severity of the internal damage.
- Your doctor will discuss with you and recommend the radiation dose that is best suited for your condition.
- Inform your doctor about your current medications or supplements.
- Inform your doctor if you have any allergies or have had previous problems with radiation therapy.
- You should not consume any solids or liquids after midnight the day before your procedure.
- Wear comfortable and loose-fitting clothes.
- Avoid wearing items such as metal items, jewelry, make-up, and contact lenses during the procedure.
- Arrange for someone to drive you home as you will not be able to drive yourself after the procedure.
- A written consent will be obtained from you after the risks and benefits of the procedure have been explained in detail.
Gamma Knife Radiosurgery Procedure
Gamma knife radiosurgery is typically performed as an out-patient procedure. The general steps include:
- First, your scalp is numbed by using a local or regional anesthesia.
- The source of the gamma radiation called a gamma knife head frame is attached to your head using small pins or screws to hold your head firmly in position during the treatment and help accurately guide the radiation beams.
- Next, you will undergo computer-guided three-dimensional imaging using MRI or CT scans while wearing the head frame.
- Information about the tumor’s dimension, size, location, and proximity to critical structures are gathered by the MRI or CT scan.
- Advanced computer software utilizes these scans to create a three-dimensional view of your anatomy and the tumor.
- The radiation machine is calibrated and prepared based on the obtained information and a treatment plan specific to your condition is formulated.
- You will be placed on the gamma knife table with your head frame in place and secured to the table to keep still.
- A radiation helmet is positioned over the head frame. It contains holes that allow only the programmed radiation from the treatment plan to pass through.
- Then the table is slid into the radiation unit.
- Your therapist operates the machine from the control room and precisely directs the radiation beams through the skin to the target area from multiple directions to destroy the tumors.
- At the completion of the procedure, the head frame is removed.
- Bandages may be applied over the pin and screw sites.
You are discharged soon after the procedure.
Care and Recovery for Gamma Knife Radiosurgery
Gamma knife radiosurgery may take a few minutes to an hour or more depending on the size and shape of the treatment area.
- You may experience swelling, pain, or tenderness from the pin sites; anti-inflammatory and pain medications are provided as needed to mitigate the discomfort.
- Most patients will be able to go home after the procedure following observation for a specified time to assess for any untoward reactions.
- Most patients will be able to return to their daily routines the following day if swelling or pain is not bothersome.
What are the Risks and Complications of Gamma Knife Radiosurgery?
Some of the risks and complications associated with gamma knife radiosurgery may include:
- Skin issues in the pin sites
- Nausea and vomiting
- Difficulty swallowing
- Loss of hair in the treatment area
- Brain swelling
What are the Benefits/Advantages of Gamma Knife Radiosurgery?
Some of the benefits of gamma knife radiosurgery include:
- High-level of safety and precision during tumor destruction
- Leaves normal, healthy brain tissue relatively intact
- Ability to penetrate deepest sections of the brain and destroy lesions not possible with conventional surgery
- Minimal risks and discomfort as it is a non-invasive procedure
- Quick recovery
- Short hospital stay for a few hours to a maximum of an overnight stay