Gamma Knife Radiosurgery for Movement Disorders
Although the lesions of pallidotomy and thalamotomy are usually created using an electrode inserted into the brain using standard stereotactic technique, these lesions can also be created with Gamma Knife radiosurgery.
This technique also involves the placement of a head frame with subsequent MRI or CT imaging to identify the target. Instead of inserting an electrode for lesion placement, the Gamma Knife directs focused radiation to the target. This creates an effective lesion for either thalamotomy or pallidotomy.
The advantage of this technique is that it is relatively noninvasive and can therefore be performed on patients whose medical condition might preclude a more invasive procedure. The disadvantage of placing lesions with Gamma Knife is the inability to perform intraoperative stimulation or microelectrode recording to verify the target. Also, there is a significant delay, ranging from months to years, in the onset of benefit. Nevertheless, in selected patients, Gamma Knife radiosurgery is an important tool in the surgical treatment of movement disorders.