What is Gamma Knife ?

What is Gamma Knife ?

Gamma Knife is provided with 201 cobalt 60 sources in the hemispheric central body, which radiate gamma ray through collimeters and precisely concentrate beams on the center of collimeter helmet. Therefore, a localized brain lesion can be treated by focused single-session external irradiation with image-guided stereotactic technique.

How Gamma Knife has been developed ?

In the 1950s, Swedish neurosurgeon, Lars Leksell, Professor of Department of Neurosurgery, Karolinska University, investigated a new method of stereotactic irradiation using proton beam to create a focused lesion in the brain. Later, he began to use gamma ray from cobalt-60 instead of proton beam because of the difficulties of proton beam in focusing. Finally, Dr. Leksell develped a machine having 200 cobalt sources in the spherical central body and named this brand-new technology as "Stereotactic gamma radiosurgery" in 1968. Initially, he used it to make a small lesion in the brain for the treatment of functional neurological diseases or psychiatric disorders. After considerable improvements including new ideas and technologies, the machine was developed as Gamma Knife. Now, Gamma Knife is used for the treatment of various intracranial lesions including brain neoplasms, both benign and malignant, and vascular anomalies such as arterio-venous malformations.

How our Gamma Knife treatments are arranged ?

Patients from any district of Japan or any other countries are welcomed. If patients will be accepted for the treatment after sufficient discussion on the indication, appointment of admission will be made. The patient will stay only for 3 days in hospital. On the first day of admission, standardized general examinations will be made. The whole procedure of Gamma Knife radiosurgery is finished during the second day. At first, neuroradiological imaging studies such as MRI, CT, or cerebral angiography is made with a stereotactic frame fixed on the patient's head under local anesthasia. Three dimensional coordinates of the target in the brain are determined for the subsequent dose planning. The treatment by Gamma Knife takes only 5 to 10 minutes for a single shot. If the target volume is large or irregular-shaped, multiple-shot technique will be done. All the procedures are carried out under fully alert condition without any discomfort except for minor tension when the head frame is fixed. The third day of the admission, the patient wil be allowed to discharge. After the treatment, periodical check-up of the treated lesion using neuroradiological imaging is necessary every 3 or 6 months until complete response is obtained. In cases of cerebral arteiro-venus mlaformation, it usually takes 2 to 3 years to evaluate the effects.