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Identification of Clinically Relevant Markers of Deep Brain Stimulation Electrode Impedance

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details. Identifier: NCT02794233
Recruitment Status : Completed
First Posted : June 9, 2016
Last Update Posted : May 15, 2018
Information provided by (Responsible Party):
University of Florida

Brief Summary:

The study will look into the changes of Deep Brain Stimulation (DBS) measured impedances in patients of Parkinson disease (PD) as a function of their functional state (lying, sitting and walking) and dopaminergic medication intake (levodopa or dopamine agonists).

The goal is to use DBS measured impedance as a surrogate of the functional and medication states of PD patients.

Condition or disease Intervention/treatment Phase
Parkinson Disease Other: Impedance measurements Not Applicable

Detailed Description:

Subjects will be recruited from the population of patients who are already implanted with DBS for treatment of PD.

At the patient's follow up visit they will be asked to come to the clinic in the "off medication" state. Off medication is defined as at least 8 hours since the last medication dosing. Data will be collected during three phases: "OFF" state, transitioning state, and "ON" state. Subjects will be asked to assume different functional states (lying, sitting or walking) for 1 minute each. During these functional states, multiple measures of impedance will be collected.

  • "OFF" state data collection: The subject will be examined to assess his motor examination score using the UPDRS-III. Measurements of impedance will be collected multiple times in the lying down and sitting up states.
  • Transition state data collection: The subject will be asked to take their dopamine medication. The medication will take approximately 1 hour to take full effect. Measurements of impedance will be collected every 10 minutes during this transition from the "OFF" state to the "ON" state. Patients will be asked to report at what point they felt the "ON: state (they can report the state as "OFF", "unsure", "transition" or "ON").
  • "ON" state data collection: The "ON" state examination will start after 1 hour from medication administration. Subjects will be examined using the UPDRS-III. Measurements of impedance will be collected in the lying down, sitting and walking states.

Summary of the study protocol:

"OFF" state Transition state "ON' state UPDRS-III x x Impedance Lying down x x Sitting up x x x Walking x UPDRS I and II x Hoehn and Yahr x x

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Study Type : Interventional  (Clinical Trial)
Actual Enrollment : 6 participants
Allocation: N/A
Intervention Model: Single Group Assignment
Masking: None (Open Label)
Primary Purpose: Other
Official Title: Identification of Clinically Relevant Markers of Deep Brain Stimulation Electrode Impedance
Study Start Date : July 2016
Actual Primary Completion Date : June 2017
Actual Study Completion Date : June 2017

Resource links provided by the National Library of Medicine

Arm Intervention/treatment
Experimental: PD patients with implanted DBS
Impedance measurements at different time points.
Other: Impedance measurements
Refer to study description

Primary Outcome Measures :
  1. Change in impedance value as it relates to the functional state. [ Time Frame: 1 hour (for both outcomes) ]
    Functional state is defined as either: lying, sitting or walking.

  2. Change in impedance value as it relates to the dopaminergic medication state. [ Time Frame: 1 hour (for both outcomes) ]
    Dopaminergic medications are defined as either levodopa containing or dopamine agonist containing medications. The state is defined as the "OFF" state (medication effect is not present) and "ON" state (medication effect noted).

Information from the National Library of Medicine

Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the contacts provided below. For general information, Learn About Clinical Studies.

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Ages Eligible for Study:   25 Years to 80 Years   (Adult, Older Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No

Inclusion Criteria:

  • Idiopathic Parkinson's patients with DBS (unilateral or bilateral)
  • Must be taking dopamine agonist or levodopa regimen
  • Medtronic Neurostimulator Activa SC, PC or PC+S (IPG)

Exclusion Criteria:

  • Hoehn and Yahr (H&Y) 4 and above
  • History of DBS revision or lead replacement surgery
  • Current or prior non-Medtronic Activa SC, PC or PC+S IPG
  • Historical information of more than 1 hour delay to "ON" state as average

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its identifier (NCT number): NCT02794233

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United States, Florida
University of Florida, Center for Movement Disorders and Neurorestoration
Gainesville, Florida, United States, 32607
Sponsors and Collaborators
University of Florida
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Principal Investigator: Leonardo Brito de Almeida, MD University of Florida
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Responsible Party: University of Florida Identifier: NCT02794233    
Other Study ID Numbers: IRB201600567
First Posted: June 9, 2016    Key Record Dates
Last Update Posted: May 15, 2018
Last Verified: May 2018
Individual Participant Data (IPD) Sharing Statement:
Plan to Share IPD: Yes
Keywords provided by University of Florida:
Deep Brain Stimulation
Electric Impedance
Parkinson disease
Additional relevant MeSH terms:
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Parkinson Disease
Parkinsonian Disorders
Basal Ganglia Diseases
Brain Diseases
Central Nervous System Diseases
Nervous System Diseases
Movement Disorders
Neurodegenerative Diseases