Pilot Study of Bilateral Pedunculo-Pontine Nucleus (PPN) Deep Brain Stimulation for Patients With Parkinson Disease (PD) Who Have Persistent Gait Disturbance, Despite Bilateral Subthalamic Nucleus (STN) Deep Brain Stimulation

Background:

• Deep brain stimulation (DBS) in the subthalamic nucleus (STN) is an approved treatment for Parkinson s disease. It stimulates a part of the brain that helps control symptoms like tremor, stiffness, and slow movements. However, many people continue to have unsteadiness and slowness while walking, trouble swallowing, and speech problems even with STN DBS. Another type of DBS focuses on a part of the brain called the pedunculopontine nucleus (PPN). PPN DBS has improved walking in some people with Parkinson's disease. Researchers want to see if combining the two types of DBS may help control symptoms better than STN DBS alone.

Objectives:

• To see if PPN DBS can help walking, balance, speaking, and swallowing in those who already have STN DBS.
• To study how the DBS combination affects brain function.

Eligibility:

• Individuals with Parkinson s disease who had STN DBS surgery at least 1 year ago, but still have difficulty walking, swallowing, and speaking.

Design:

• Participants will be screened with a physical exam and medical history. They will also have neurological tests and other tests to measure Parkinson s disease symptoms.
• This study requires eight visits over 1 year. One of the visits will be a 9- to 10-day admission to the NIH Clinical Center for DBS surgery.
• Participants will have PPN DBS surgery. The surgery will be done in two steps. In the first step, the leads will be placed in the brain. In the second step, 1 week later, the stimulator device will be placed in the chest or abdomen.
• One month after the surgery, participants will have a study visit to program the PPN DBS device to find settings that will improve walking and balance.
• Participants will have study visits 2, 3, 6, and 12 months after surgery. Each visit will be used to check the stimulators and make any adjustments needed to try to improve walking and balance or to lessen side effects. Participants will have tests of walking and balance, speech, and swallowing. Some tests will be done with different combinations of the stimulators on or off to see the effects of each set of stimulators.