Leksell Gamma Knife Icon

What’s Gamma Knife
Gamma Knife is an intracranial stereotactic radiosurgery technique that allows to intervene on many tumors and brain pathologies in a mini-invasive mode.  It is defined radiosurgery since the results obtained are similar to the ones of a surgical intervention, but it’s actually a type of radiotherapy that does not require any incision or opening of the skull.  In fact the machinery is based on the administration of high radiation doses, which reach as accurately as possible brain injuries requiring an intervention, without harming the neighbouring structures.

Treated pathologies
According to clinician’s recommendations, Gamma Knife radiosurgery can be used  for the treatment of the following pathologies: 

• Malignant and benign, primitive brain tumors (including acoustic neuromas , meningiomas, pituitary adenomas, ….) 
• Brain metastases
• Uveal melanomas
• Arteriovenous malformations
• Trigeminal neuralgia
• Parkinson’s disease
• Epilepsy 

 
Gamma Knife general benefits
If compared to the traditional surgical treatment, Gamma Knife radiosurgery drastically reduces the risk of complications connected with the surgical procedure.  It also enables to:

• reach pathologies located in deep areas of the skull and therefore inoperable through other methods;
• intervene on patients, whose clinical conditions cannot bear any surgical procedure.

Further advantages, in addition to the above ones, are to be mentioned concerning the phases after the surgery: 

• Hospitalization times are noticeable reduced. They are about 1 – 2 days, versus the period of two weeks provided for by the traditional surgery; 
• No  post-surgical rehabilitation is necessary.   

Leksell Gamma Knife Icon Specific Advantages 
Gamma Knife radiosurgery has been used for about 40 years; over the last ten years important new features have been introduced in terms of precision and accuracy; however, the greatest innovation is represented by the brand new Leksell Gamma Knife Icon model, with which right Fondazione Poliambulanza was equipped for the first time in Italy.
Such latest generation model allows to intervene on brain pathologies treated by previous model as well, but with some innovations:

• Greater accessibility to cranial areas: with Icon model it is also possible to treat multiple lesions dislocated in peripheral cerebral areas, thus increasing the number of treatable diseases by about 20%.
• Higher customization of treatment: Leksell Gamma Knife Icon is equipped with an innovative collimation system designed to automatically manage the position of radiant sources, thus allowing to obtain radiation beams with a different diameter even for the same isocenter.     
• Non-invasive repositioning system:  up to the introduction of Icon model, to carry out Gamma Knife treatment, it was necessary to fix a stereotactic helmet to patient's head throgh four screws.  Now, it’s currently possible to adopt also a non-invasive fastening system, which uses thermoplastic masks and which does not require any anesthesia or skin lesion. 
• Presence of integrated stereotactic Imaging: The phases of positioning and monitoring of treatment are made possible through the arrangement of a Stereotactic Imaging system consisting of: 
  • A CT Cone Beam integrated into the system, which is used to check patient’s position before each session; 
  • An Adaptive Dose Control: a system that adapts the treatment plan to the daily situation combined with an infrared monitoring system that checks the patient’s position throughout the treatment.  (In fact should the patient move beyond the tolerance limit established by the system, the irradiation of gamma rays would stop to resume only after the recovery of the established conditions).  
• Possibility of treatment in multiple, shorter sessions. 

To undergo Gamma Knife treatment
If the patient or his/her medical practitioner think that Gamma Knife may represent a chance of treatment, it’s necessary to perform an outpatient evaluation with a specialist physician in Poliambulanza.
On such occasion, it's useful for the patient to bring with him/her a recent brain magnetic resonance imaging (or a TC when unable to undergo a MRI) and any other examination that may complete his/her medical history.

The phases of the treatment
The implementation of Leksell Gamma Knife Icon treatment always provides for the multidisciplinary interaction among radiotherapist, neurosurgeon, neuroradiologist  and a health physician.  It takes place in four phases, each of which is totally  painless:

1. The stereotactic helmet or the thermoplastic mask  (depending on the needs and the instructions outlined by the doctors) are applied to patient’s head, in order to determine exactly the area to be radiated;  
2. The brain of the patient is mapped through  imaging procedures, such as Magnetic Resonance Imaging (MRI), Computerized Tomography (CT), Brain Angiography;  
3. After the imaging, the multispecialist team establishes the treatment plan and the dose of radiation; 
4. The treatment is carried out, of which the duration may be different. 

Preparation and side effects 
No general examinations, such as electrocardiogram and blood sampling, are necessary before treatment. Depending on the type of injury to be treated the patient may be required to perform an audiometric examination, eye examination or other specific examinations specially indicated by the physician.

The day of treatment is necessary: 

• fasting from the previous midnight; 
• wear comfortable clothes; 
• remove jewelery, hair products, make-up, artificial nails, prostheses or wigs. 

The following events should also be reported in advance to the doctor:

• use of medications;
• allergies;
• presence of medical devices (such as stents, heart valves, pacemakers).

It is fundamental to inform the doctor even about the suspicion of a pregnancy, since the exposure to radiation may harm the fetus.

Possible side effects associated with Gamma Knife treatment, that however are rare, are: 

• headache; 
• nausea;
• cerebral edema (with possible alteration of some neurological functions); 
• epileptic seizures;
• general numbness; 
• temporary hair loss near the treated area. 

In any case, prior to Gamma Knife treatment, in the course of an in-depth interview, the patient will be provided with all the necessary information as well as the possible risks related to his/her specific problem.
 

Contacts
To contact the Operating Unit of Neurosurgery: 
Phone No.:  030 3518207
Email address: nch.segreteria@poliambulanza.it