This is primarily a safety protocol to evaluate the safety of unilateral subthalamotomy using
Transcranial ExAblate in a staged, escalating dose titration manner; Stage I is
subtherapeutic; Stage II is full, therapeutic unilateral lesioning.
The medication-refractory motor symptoms and medication-induced side effects of advance
Parkinson's disease can be safely treated with unilateral, staged subthalamotomy as performed
with ExAblate Neuro Transcranial system. This staged approach of performing a
subtherapeutic/test lesion first will identify patients who are at risk for involuntary
movements following subthalamic ablation.
Data will be collected to establish the basic safety and clinical efficacy of this type of
treatment as the basis for later studies that will evaluate the full clinical efficacy.
1. Men and women, age 30 years and older
2. Subjects who are able and willing to give informed consent and able to attend all
study visits through 24 Months
3. Subjects with a diagnosis of idiopathic PD by UK Brain Bank Criteria as confirmed by a
movement disorder neurologist at the site
4. Levodopa responsive as defined by at least a 30% reduction in MDS-UPDRS motor subscale
in the ON vs OFF medication state.
5. Disabling motor complications of PD on optimum medical treatment characterized
dyskinesia or motor fluctuations
6. Predominant disability from one side of the body (i.e unilateral or markedly
asymmetric disease) as determined by movement disorders neurologist and neurosurgeon
7. Subjects should be on a stable dose of all PD medications for 30 days prior to study
8. Subthalamic nucleus is visible on MRI so that it can be targeted by the ExAblate
9. Subjects should have a Screening motor assessment of ≥ 40 while off medications on the
10. Subject is able to communicate sensations during the ExAblate Transcranial procedure.
1. Hoehn and Yahr stage in the ON medication state of 2.5or greater
2. Presence of 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.
3. Any suspicion that Parkinsonian symptoms are a side effect from neuroleptic
4. Subjects who have had deep brain stimulation or a prior stereotactic ablation of the
5. Unstable psychiatric disease, defined as active uncontrolled depressive symptoms,
psychosis, delusions, hallucinations, or suicidal ideation. Subjects with stable,
chronic anxiety or depressive disorders may be included provided their medications
have been stable for at least 60 days prior to study entry and if deemed appropriately
managed by the site neuropsychologist
6. Legal incapacity or limited legal capacity as determined by the neuropsychologist
7. Subjects exhibiting any behavior(s) consistent with ethanol or substance abuse as
defined by the criteria outlined in the DSM-IV as manifested by one (or more) of the
following occurring within the preceding 12 month period:
1. Recurrent substance use resulting in a failure to fulfill major role obligations
at work, school, or home (such as repeated absences or poor work performance
related to substance use; substance-related absences, suspensions, or expulsions
from school; or neglect of children or household).
2. Recurrent substance use in situations in which it is physically hazardous (such
as driving an automobile or operating a machine when impaired by substance use)
3. Recurrent substance-related legal problems (such as arrests for substance related
4. Continued substance use despite having persistent or recurrent social or
interpersonal problems caused or exacerbated by the effects of the substance (for
example, arguments with spouse about consequences of intoxication and physical
8. Subjects with unstable cardiac status including:
1. Unstable angina pectoris on medication
2. Subjects with documented myocardial infarction within six months of protocol
3. Significant congestive heart failure defined with ejection fraction < 40
4. Subjects with unstable ventricular arrhythmias
5. Subjects with atrial arrhythmias that are not rate-controlled
9. Severe hypertension (diastolic BP > 100 on medication)
10. History of or current medical condition resulting in abnormal bleeding and/or
11. 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
12. Patient 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;
13. Subjects with standard contraindications for MR imaging such as non-MRI compatible
implanted metallic devices including cardiac pacemakers, size limitations, etc.
14. Significant claustrophobia that cannot be managed with mild medication.
15. Subjects who are not able or willing to tolerate the required prolonged stationary
supine position during treatment.
16. History of intracranial hemorrhage
17. History of multiple strokes, or a stroke within past 6 months
18. Subjects with a history of seizures within the past year
19. Subjects with brain tumors
20. Subjects with intracranial aneurysms requiring treatment or arterial venous
malformations (AVMs) requiring treatment.
21. Are participating or have participated in another clinical trial in the last 30 days
22. Any illness that in the investigator's opinion preclude participation in this study.
23. Subjects unable to communicate with the investigator and staff.
24. Pregnancy or lactation.