This equipment makes it possible to treat numerous brain lesions in which surgical or radiotherapy treatment with traditional techniques involves a high mortality or infection rate, mainly due to the depth and inaccessibility of the lesion or its nearness to arteries, nerves and other vital structures.
Indeed it allows hitting the target without having to open the skull. To do so, numerous gamma rays are used, emitted from cobalt-60 sources arranged in a hemispherical array in order to direct the rays at a single point. Thanks to the use of a large number of beams (each carrying a “low” radiation dose) which join at a single point, it is possible to hit the target with a high dose of radiation, at the same time delivering a very low dose to the surrounding healthy tissues. Thus it is distinguished from traditional radiation therapy by the targeted, non-massive method of irradiation.
The Gamma Knife is used to treat the majority of malign and benign tumours, in vascular indications and in functional disorders. Its usage is especially widespread for the treatment of: arteriovenous malformations, malformations of the cavernous sinus, acoustic neurinomas, trigeminal neurinomas, meningiomas, single and multiple metastases.
The use of gamma rays as a tool offers advantages like the reduction in risk of infection, the elimination of complications due to the impact of the operation - hospitalisation times are reduced from the 2 weeks required on the average for traditional surgery, to 2 days, one before and one after the treatment - and the possibility of treating otherwise inoperable cases. In addition, the treatment may vary from 30 minutes to a few hours and only requires a single session. This means that the patient does not have to return, except for the normal follow up. Finally, it does not require shaving hair or general anaesthesia. There are only 300 of them in the world for one million patients, and one of them is found at Maria Cecilia Hospital.