Phase II Subthalamic Nucleus (STN) vs. Globus Pallidus (GPi) Trial
Condition: Parkinson's Disease
MeSH terms: Parkinson Disease
Intervention: Bilateral Deep Brain Stimulation
Intervention description: The DBS site (STN or GPi) was assigned on a random basis at the time the patient enters the surgical phase of the trial.
Phase: Phase 3
Study type: Interventional
Primary purpose: Treatment
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Single (Participant)
Enrollment: 299.0
Sex: All
Minimum age: 22 Years
Healthy volunteers: No
Keywords: Parkinson's Disease; levo-dopa; tremor; dyskinesia; subthalamic nucleus; globus pallidus

Summary:

      The goal of the second phase of the study is to determine if simultaneous bilateral
      subthalamic nucleus stimulation or simultaneous bilateral globus pallidus stimulation is more
      effective in reducing symptoms of Parkinson's Disease.
    

Eligibility criteria:

        Inclusion Criteria:

          -  idiopathic Parkinson's Disease

          -  Hoehn and Yahr stage 2 or worse when off medications

          -  L-dopa responsive with clearly defined "on" periods (i.e. symptoms improve at least
             partially with L-dopa administration, a characteristic that helps distinguish
             idiopathic PD from "Parkinson's Plus" and atypical Parkinson's syndromes-see below)

          -  persistent disabling symptoms (e.g. on troubling dyskinesias, or disabling "off"
             periods at least 3 hours/day) despite medication therapy. Patients will have been
             treated with variable doses of levodopa and dopamine agonists (at a minimum) and will
             have had an adequate trial of other adjunctive medications)

          -  stable on medical therapy for at least one month prior to study enrollment

          -  age >21

          -  available and willing to be followed-up according to study protocol

        Exclusion Criteria:

          -  "Parkinson's plus" syndromes, secondary, or atypical Parkinson's syndromes (e.g.
             progressive supranuclear palsy, striato-nigral degeneration, multiple system atrophy,
             post-stroke, post-traumatic, or post-encephalitic Parkinson's. These patients have
             cardinal symptoms characteristic of PD but with additional symptoms indicating other
             organic brain dysfunction, such as gaze palsies, autonomic dysfunction, lack of
             response to L-dopa, these individuals tend not to improve with standard treatments for
             PD)

          -  previous Parkinson's Disease surgery

          -  medical contraindications to surgery or stimulation (e.g. uncontrolled hypertension,
             advanced coronary artery disease, other implanted stimulation or
             electronically-controlled devices including cardiac demand pacemaker, aneurysm clips,
             cochlear implants, or a spinal cord stimulator) (Note: for the subject who receives
             either a pacemaker and/or defibrillator after this study enrollment, he/she will be
             allowed to continue the study if the neurostimulator system can be adequately
             programmed to permit system compatibility)

          -  contraindication to magnetic resonance imaging (e.g. indwelling metal fragments or
             implants that might be affected by MRI)

          -  active alcohol or drug abuse

          -  score on Mini-Mental Status examination of 24 or lower, or other neuropsychological
             dysfunction 9e.g. dementia) that would contraindicate surgery

          -  intracranial abnormalities that would contraindicate surgery (e.g. stroke, tumor,
             vascular abnormality affecting the target area)

          -  pregnancy

          -  concurrent participation in another research protocol