Gamma Knife radiosurgery is a technique that uses intracranial stereotactic radiosurgery. It may be helpful in treating vascular lesions such as cavernous angioma

What is Gamma Knife radiosurgery for cavernous angioma?

Commonly known as cavernoma, cavernous aginoma can break and cause bleeding into the brain tissue. If the episode occurs only once, the risk of re-bleeding is very low (approximately 1% per year per person); however, after a second bleeding, risk grows higher, up to 30% per year. Cases that involve bleeding into the brain tissue can cause symptoms similar to those caused by AVM.

How is Gamma Knife radiosurgery for cavernous angioma performed?

The patient is lightly sedated and then given a local anesthesia, where the stereotactic frame is placed to subject the patient to imaging tests (brain MRI with gadolinium). The images will allow the specialist to plan for the most proper form of treatment. Once decided upon, the patient will lay with a stereotactic frame fixed onto the Gamma Knife bed. The treatment can last from one to six hours, depending on the needs of the patient and the target area for radiation.

What are the advantages to undergoing Gamma Knife radiosurgery for cavernous angioma?

Gamma Knife radiosurgery is a minimally invasive procedure , done in a single session and free of pain and surgical incisions. The procedure is almost always done on an outpatient basis and the patient is usually discharged the very same day.  

Is Gamma Knife radiosurgery for cavernous angioma painful and / or dangerous?

The procedure is not painful, though the patient may feel pain during positioning of the four small metal pins to stabilize the helmet. During the actual treatment, the patient will undergo subtle movements of the head, though they will not experience any pain or noises.  The risks associated with this procedure are: neurological disorders (estimated risk <5%), brain edema (estimated risk <5%); seizures (estimated risk <5%); infection of the superficial tissues (estimated risk <1%); radioindotta cancer (the risk is 10,000 in a time period ranging from 5 to 30 years).

Which patients can undergo this procedure? 

Patients who have cavernous angioma less than 4cm in size can undergo this procedure. A neurosurgeon will visit the patient to confirm the indication for treatment.


The results of the procedure are not immediate . The patient will be informed of any additional examinations that need to be carried out during discharge.  The radiation effect can take effect after months and / or years. Sometimes, Gamma Knife treatment may not be enough and additional treatment may be necessary, such as Gamma Knife combined with surgery.

What steps should be taken to help prepare for this procedure?

A few days before undergoing the procedure, the patient will travel to Humanitas for pre-admission and will be subjected to a blood test, an electrocardiogram (ECG), and a medical examination for a complete compilation of medical records. It is important that the patient announce any allergies to medications or contrast agents, or claustrophobia. On the day of the procedure, the patient should be accompanied by a family member or an acquaintance and should have been fasting from midnight the night before. On the night before the procedure, the patient should cleanse themselves with a product-based disinfectant shampoo, such as chlorhexidine. It is best to avoid wearing any jewelry: brooches, hairpins, makeup, hair products, and artificial nails; but rather wear comfortable clothing and footwear, preferably with buttons or zippers.