Magnetic Resonance (MR) Guided Functional Ultrasound-Neurosurgery for Movement Disorders

Inclusion Criteria: * Men and women, between 18 and 80 years, inclusive. * Patients who are able and willing to give consent and able to attend all study visits. * A diagnosis of a MD, such as Essential Tremor (ET), Idiopathic Parkinson's diseases or primary Dystonia as confirmed from clinical history and examination by a movement disorder neurologist. * A MD refractory to adequate medical treatment, or in whom the indication for Deep Brain Stimulation (DBS) would be given, but DBS cannot be performed because of medical comorbidities or medical reasons, or because the patient clearly confirms by written statement that he does not want to undergo DBS for personal reasons (PD: increasing motor fluctuations albeit optimal medical treatment \& unbearable side effects of medication; ET: failure of adequate tremor control with Propranolol and Primidone alone and in combination; Dystonia: dystonia or pain not controlled by oral medication). An adequate medication trial is defined as a therapeutic dose of each medication or the development of side effects as the medication dose is titrated. * Either the medial thalamic nuclei or the subthalamic or pallidal areas can be target by the ExAblate device. The target region must be apparent on MRI such that targeting can be performed with either direct visualization or by measurement from landmarks, using the "Stereotactic Atlas of the Human Thalamus and Basal Ganglia" by Anne Morel, 39 analogous to our first clinical FUS study on patients…