Clinical Outcomes of Gamma Knife Radiosurgery in the Treatment of Patients with Tremors

Patients who suffer from tremors are initially treated with pharmecuticals. Although medication has proven to be effective in achieving tremor control for some patients, there is still a fraction of patients who seek neurosurgical alternatives due to unacceptable tremor relief or side-effects from the prescribed drugs. Invasive neurosurgical procedures include radiofrequency thalamotomy and in recent years deep brain stimulation. However, patients who have advanced cardiac or respiratory disease, patients who use anticoagulants and patients who are of advanced age are not qualified candidates for neurosurgery. An alternative modality for lesioning intracranial structures is stereotactic radiosurgery using the Gamma Knife. The Gamma Knife is a Cobalt-60 based machine, with 201 separate 4 to18 mm collimator openings that emits multiple gamma rays that converge on a focal point in the brain specified by computer planning. Since its introduction by Leksell, the role of Gamma Knife radiosurgery as a management approach for patients diagnosed with tremors is continuously increasing. This article will review the efficacy of GKRS in the management of tremors, as well as describe the treatment planning and methods associated with this evolving treatment strategy.