ExAblate Transcranial MR Guided Focused Ultrasound for the Treatment of Parkinson's Disease

Subjects who sign informed consent and pass all eligibility criteria will be randomized to a
treatment assignment. During treatment, the assigned treatment (ExAblate Transcranial or Sham
ExAblate Transcranial)will be delivered. Subjects are followed in a blinded fashion for three
(3) months. After the 3-month assessment, subjects will be unblinded and told their treatment
assignment. Subjects receiving Sham ExAblate Transcranial treatment who still meet criteria
will be crossed over and receive an active ExAblate Transcranial treatment. Subjects will be
followed for up to two (2) years. Follow-up at 1 week, 1 month, 3 months, 6 months, 9 months,
12 months and up to two (2) years includes Unified Parkinson's Disease Rating Scale (UPDRS)
scoring, mental and cognitive functional testing and questionnaires.

Inclusion Criteria:

- Men and women, age 30 years and older

- Subjects who are able and willing to give informed consent and able to attend all
study visits

- Subjects with a diagnosis of idiopathic PD as confirmed from clinical history and
examination by a movement disorder neurologist at the site

- Subject demonstrates a severe resting tremor or postural/action as measured by UPDRS

- Subject exhibits a significant disability from their PD tremor despite medical
treatment

- Subjects should be on a stable dose of all PD medications for 30 days prior to study
entry

- Subject is able to communicate sensations during the ExAblate Transcranial procedure

Exclusion Criteria:

- Subjects with unstable cardiac status

- Subjects exhibiting any behavior(s) consistent with ethanol or substance abuse

- Severe hypertension

- Subjects with standard contraindications for MR imaging such as non-MRI compatible
implanted metallic devices including cardiac pacemakers, size limitations, etc.

- Known intolerance or allergies to the MRI contrast agent including advanced kidney
disease or severely impaired renal function

- Significant claustrophobia that cannot be managed with mild medication

- Current medical condition resulting in abnormal bleeding and/or coagulopathy

- 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

- History of intracranial hemorrhage

- History of multiple strokes, or a stroke within past 6 months

- Subjects who are not able or willing to tolerate the required prolonged stationary
supine position during treatment

- Are participating or have participated in another clinical trial in the last 30 days

- Subjects unable to communicate with the investigator and staff

- Subjects with a history of seizures within the past year

- Subjects with brain tumors

- Subjects with intracranial aneurysms requiring treatment or arterial venous
malformations (AVMs) requiring treatment

- Subjects who have had deep brain stimulation or a prior stereotactic ablation of the
basal ganglia