Criteria
Inclusion Criteria:
Men and women, age 30 years and older, desiring bilateral treatment option with second side staged at 6 months.
Subject is able and willing to give informed consent and able to attend all study visits
Subject with a diagnosis of idiopathic PD by UK Brain Bank Criteria as confirmed by a movement disorder neurologist at the site.
Subject has Levodopa responsive as defined by at least a 30% reduction in MDSUPDRS motor subscale in the ON vs OFF medication state.
Subject has MDS-UPDRS score of 30 or greater in the meds OFF condition.
Motor complications of PD on optimum medical treatment characterized dyskinesia (MDS-UPDRS item 4.2 score of 2 or greater in the meds ON condition) OR Motor fluctuations (MDS-UPDRS item 4.4 score of 2 or greater in the meds ON condition)
Subject is on a stable dose of all PD medications for 30 days prior to screening visit PD assessments as determined by medical records
Subject is able to communicate sensations during the Exablate procedure.
Subject's Pallido-thalamic region can be targeted by the Exablate device.
Exclusion Criteria:
Subject has a score of 3 or greater on the PULL test.
Subject with severe premorbid risks as specified in the MDS-UPDRS Part II subsection motor aspects of experiences of daily living scores: 3 or 4 on question 2.1 (speech) OR 3 or 4 on question 2.3 (chewing and swallowing) OR 4 on question 2.2 (saliva and drooling).
Subject where there is suspicion that Parkinsonian symptoms are a side effect from neuroleptic medications.
Subject with significant cognitive impairment as determined by the neuropsychologist.
Subject has other central neurodegenerative disease suspected on neurological examination. These include: multisystem atrophy, progressive supranuclear palsy, corticobasal syndrome, dementia with Lewy bodies, and Alzheimer's disease.
Subject with unstable psychiatric disease, defined as active uncontrolled depressive symptoms, psychosis, delusions, hallucinations, or suicidal ideation
Women of childbearing potential who are pregnant or lactating
Subjects exhibiting any behavior(s) consistent with ethanol or substance abuse
Subject with unstable cardiac status or severe hypertension including:
Documented myocardial infarction within six months of enrollment
Unstable angina on medication
Unstable or worsening congestive heart failure
Left ventricular ejection fraction below the lower limit of normal
History of a hemodynamically unstable cardiac arrhythmia
Cardiac pacemaker
Diastolic BP > 100 on medication
Subject with history of abnormal bleeding, hemorrhage, or coagulopathy including:
Subject with risk factors for intraoperative or postoperative bleeding as indicated by: platelet count less than 100,000 per cubic millimeter; a documented clinical coagulopathy; or INR coagulation studies exceeding the institution's laboratory standard.
History of intracranial hemorrhage, multiple strokes, or a stroke within past 6 months
Subjects with intracranial aneurysms requiring treatment or arterial venous malformations (AVMs) requiring treatment
Subject is receiving anticoagulant (e.g., warfarin) or antiplatelet (e.g., aspirin) therapy within one week of focused ultrasound procedure or drugs known to increase risk or hemorrhage (e.g., Avastin) within one month of focused ultrasound procedure.
Subject with severely impaired renal function with estimated glomerular filtration rate <30 mL/min/1.73m2 (or per local standards should that be more restrictive) and/or who is on dialysis.
Subjects with a history of seizures within the past year.
Subject with an intracranial brain tumor
Subjects with life-threatening systemic disease that include and not limited to the following will be excluded from the study participation: HIV, liver failure, blood dyscrasias, etc.
Any illness that in the investigator's opinion preclude participation in this study.
Subject with standard contraindications for MR imaging such as implanted metallic devices
Subject who had prior deep brain stimulation of the basal ganglia or thalamus.
Subjects who are unable to tolerate the required prolonged stationary supine position during treatment.
Subjects who have an Overall Skull Density Ratio of less than 0.40 as calculated from the screening CT.
Subject who is participating in another clinical investigation with an active treatment arm in the last 30 days.
Subject who is unable to communicate with the investigator and staff. Additional Exclusion Criteria for Staged Bilateral PTT procedure
Subject who had moderate to severe neurological event such as dysphagia, speech, gait imbalance, cognitive impairment, and visual field deficit following index procedure.