Radiosurgery for Movement Disorders

Lesioning, or the destruction of specific brain targets, has long been utilized in neurosurgery for the treatment of movement disorders. During the mid-twentieth century, movement disorder surgery transitioned from traditional open surgery to less invasive means with the advent of modern frame-based stereotaxy. Lars Leksell, one of the pioneers of stereotaxy, implemented a frame-based stereotaxy for a novel use: delivery of single-session, transcranial radiation. While Leksell's original aim for radiosurgery was for functional disorders such as pain, radiosurgery soon became increasingly utilized in the treatment of oncologic and neurovascular disease. The success of radiosurgery in treating these diseases along with developments in technology and imaging has renewed interest in radiosurgical lesioning for the treatment of movement disorders. Movement disorders such as essential tremor and Parkinson disease have been treated with radiosurgical thalamotomy with promising results. Small prospective trials have demonstrated up to a 50% reduction in tremor with minimal side effects. While such results are encouraging, compared to other procedures for the treatment of movement disorders (e.g., deep brain stimulation), radiosurgery lacks the ability to confirm treatment effect and ensure the absence of side effects given the nature of radiation's onset delay. Despite this drawback, radiosurgery may be appealing in certain patients given its noninvasive nature allowing for the treatment of patients deemed medically unsuitable for procedures such as deep brain stimulation. Ultimately, radiosurgery represents one more tool within the neurosurgeon's armamentarium for the treatment of movement disorders; the decision to offer radiosurgery requires weighing the risks and benefits of each procedure as they apply to each unique patient.