Scalar Closed Loop Intraoperative Study

March 6, 2020 updated by: Dennis Turner, M.D.

Scalar Closed-Loop STN/GPi DBS Based on Evoked and Spontaneous Potentials (Intraoperative Studies)

The purpose of this study is to measure neural activity during deep brain stimulation (DBS). There are two types of neural activity that we will record from DBS electrodes during this study: DBS local evoked potentials (DLEPs) and spontaneous, local field potentials (LFPs). We will measure the effects of varying stimulation parameters on both the neural activity and changes in motor symptoms -- bradykinesia and tremor -- in subjects with Parkinson's disease (PD). Correlating neural activity characteristics with changes in symptoms will improve our understanding of the mechanisms of action of DBS. This intraoperative study will specifically compare our ability to record neural activity using circuitry developed at Duke for this purpose [Kent et al, 2015] to a new, implanted pulse generator (IPG; RC+S) developed by Medtronic. These intraoperative studies will specifically test a preliminary version of the RC+S (that is not designed for implantation), and will lead to a clinical trial assessing the efficacy of the implantable RC+S IPG in PD patients once this device is available and approved for this trial.

Study Overview

Status

Status

Indicates the current recruitment status or the expanded access status.
Completed

Conditions

Conditions

The disease, disorder, syndrome, illness, or injury that is being studied. On ClinicalTrials.gov, conditions may also include other health-related issues, such as lifespan, quality of life, and health risks.

Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.

Detailed Description

The investigator will measure DBS local evoked potentials (DLEPs) and/or local field potentials (LFPs) together with motor symptoms (tremor and/or bradykinesia) in response to deep brain stimulation (DBS). The study will be conducted in the operating room at Duke University Medical Center. Additional operating room costs will be covered by institutional resources at Duke. The study will be performed on subjects who are undergoing implantation of the DBS system during an awake, stereotactic procedure for PD.

The subject group will only include patients undergoing a DBS implant procedure for PD. The surgical procedure will proceed as needed for treatment of Parkinson's disease (PD), including implantation of the DBS electrode (one into STN or dual electrodes into STN and GPi/GPe) into the targeted regions of the brain. For this research, subjects will receive temporary (~45 min) percutaneous extensions to the DBS electrode(s) and DBS lead cannula after implantation. These temporary extensions will connect to both our Duke stimulation and recording system or the Medtronic RC+S test recording system, alternating as needed, to allow recording and direct comparison of neural DLEP responses and/or LFPs using the two different stimulation/recording systems. Details of the stimulation and recording system are provided in the Study Interventions section. After the study is completed, the second DBS electrode (if placed) and the temporary percutaneous extensions will be removed. Then, the ordinary clinical conduct of the procedure will continue for treatment of the patient's movement disorder.

The investigator will measure tremor and/or bradykinesia in persons with PD during DBS. Subjects will be familiarized with and able to practice the evaluation tasks before preparation for surgery. Further, they will be asked to discontinue use of dopaminergic and/or anti-tremor medications overnight prior to the study (as is the clinical routine), to reduce variability of motor symptoms due to the time course of medications. The investigator will conduct evaluations using unilateral stimulation, with the limb contralateral to the side of stimulation used for measurement of motor symptoms. Subjects may also be asked to rate any side effects that they experience on a 0 - 10 scale.

Contacts on the subject's DBS electrode will be used for stimulation and recording. The four DBS contacts are designated as 0-1-2-3 in the ventral-dorsal direction. For monopolar stimulation, a single contact will be used for cathodic stimulation (1- or 2-) and a conductive pad will be placed on the subject's skin, outside of the sterile field, to serve as the return electrode. The recording contacts will be two other contacts on the DBS lead. For bipolar stimulation, DBS pulses will be applied between two electrode contacts, and the recording contacts will be the two remaining free contacts. The stimulus waveform will be a charge-balanced biphasic pulse, with charge restricted to values below the limit set by the manufacturer, 30 µC/cm2. Another conductive pad will be placed on the subject to serve as the recording reference. For subjects undergoing the DBS implantation surgery, the DBS lead cannula or a surgical retractor normally placed at the cranial incision site may also be used as the recording reference or return electrode.

In subjects with tremor-dominant PD, the investigator will record both the tremor and DLEP and/or LFP responses from the DBS electrode. Several trials will be conducted with different stimulation amplitudes, frequencies (≤185 Hz), temporal patterns, and contact configurations. The stimulation amplitude will be less than that identified to be uncomfortable to the subject or that generates side effects, as determined by a neurologist and/or neurosurgeon during the initial testing phase following implantation. The different stimulation parameters will be delivered in randomized order, and the subject will be blinded to the parameters. Measurements will be made during 2-minute trials, in which stimulation will be off for the first minute of the trial, and on for the remaining minute. At 30 s into both the off (baseline) and on phases of the trial, tremor will be measured for 20 s. The neural activity will also be measured from the electrode during both the off and on phases. The total amount of time necessary for data collection will be about 45 minutes.

Tremor will be measured using an accelerometer taped to the back of the subject's hand, and with the wrist extended such that the hand is parallel to the forearm. The elbow may either be supported or unsupported, depending on which induces greater tremor (determined prior to any trials in each subject). Tremor as measured by an accelerometer correlates well with clinical tremor rating scales [Elble et al, 2006].

In subjects with Parkinson's disease who do not have dominant tremor symptoms, the investigator will record both bradykinesia testing responses and DLEP and/or LFP potentials. Several trials will be conducted with different stimulation amplitudes, mean frequencies (≤185 Hz), temporal patterns, and contact configurations. The maximum amplitude delivered will be determined as described as above. The different stimulation parameters will be delivered in randomized order, and the subject will be blinded to the parameters. Measurements will be made in 10-minute trials, in which stimulation will be off for the first five minutes of the trial, and on for the remaining five minutes. At approximately 90, 210 and 250 s into both the off (baseline) and on phases of the trial, bradykinesia will be measured for 20 s. The neural activity will also be measured from the electrode during both the off and on phases of the trial. The total amount of time necessary for data collection will be about 45 minutes.

For bradykinesia measurements, the subject will be instructed to press alternately the right and left buttons of a computer mouse with the index and middle finger of their hand as rapidly and regularly as possible. Bradykinesia will be measured as the timing of alternating finger presses, a validated test of bradykinesia [Taylor-Tavares et al., 2005].

Before DBS surgery, the subject's baseline pathological motor symptoms may be assessed in the pre-operative setting, to familiarize the patient with the task ahead of the implant procedure. Tremor or bradykinesia will be measured using the previously-described accelerometer measurement or the mouse click task, respectively. This task will take about 5 minutes, and will be performed in the DBS-off condition. No sedation will be administered until after this has been completed.

Following DBS surgery, the subject's pre-operative MRI and post-operative high-resolution CT scans may be used to determine the location of DBS electrode contacts within the brain. Placement of the electrode during DBS implant surgery will not be altered by the research study.

Study Type

Study Type

Describes the nature of a clinical study. Study types include interventional studies (also called clinical trials), observational studies (including patient registries), and expanded access.
Interventional

Enrollment (Actual)

Enrollment

The number of participants in a clinical study. The "anticipated" enrollment is the target number of participants that the researchers need for the study.
5

Phase

Phase

The stage of a clinical trial studying a drug or biological product, based on definitions developed by the U.S. Food and Drug Administration (FDA). The phase is based on the study's objective, the number of participants, and other characteristics. There are five phases: Early Phase 1 (formerly listed as Phase 0), Phase 1, Phase 2, Phase 3, and Phase 4. Not Applicable is used to describe trials without FDA-defined phases, including trials of devices or behavioral interventions.
  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

  • United States
    • North Carolina
      • Durham, North Carolina, United States, 27710
        • Duke University Medical Center

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Eligibility Criteria

The key requirements that people who want to participate in a clinical study must meet or the characteristics they must have. Eligibility criteria consist of both inclusion criteria (which are required for a person to participate in the study) and exclusion criteria (which prevent a person from participating). Types of eligibility criteria include whether a study accepts healthy volunteers, has age or age group requirements, or is limited by sex.

Ages Eligible for Study

18 years to 80 years (ADULT, OLDER_ADULT)

Accepts Healthy Volunteers

No

Genders Eligible for Study

All

Description

Inclusion Criteria:

  • Parkinson's disease (PD) patients who are scheduled to already undergo the planned deep brain electrode placement for treatment of their movement disorder at Duke University Medical Center.
  • Able to understand the study and consent form, and interested in proceeding with research during the invasive brain surgery to receive a DBS system for treatment of PD.

Exclusion Criteria:

  • Inability to execute the motor tasks during the study.

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: OTHER
  • Allocation: NA
  • Interventional Model: SINGLE_GROUP
  • Masking: NONE

Arms and Interventions

Participant Group / Arm

Participant Group / Arm

A group or subgroup of participants in a clinical trial that receives a specific intervention/treatment, or no intervention, according to the trial's protocol.
Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.
OTHER: Intraoperative Recording During DBS Implant Surgery
Participants will be recruited and enrolled from individuals who have Parkinson's disease (PD) and who already are scheduled to undergo the planned deep brain electrode placement for treatment of their movement disorder. Intraoperative recordings of participants' neural signals will be made through the implanted deep brain electrode(s).
Device: IPG; RC+S
We will measure the effects of varying stimulation parameters on the neural activity in subjects with Parkinson's disease (PD).

What is the study measuring?

Primary Outcome Measures

Primary Outcome Measures

In a clinical study's protocol, the planned outcome measure that is the most important for evaluating the effect of an intervention/treatment. Most clinical studies have one primary outcome measure, but some have more than one.
Outcome Measure
Measure Description
Time Frame
Number of Participants With Recorded Evoked Neural Signals From Deep Brain Stimulation (DBS) Electrodes During DBS for Parkinson's Disease.
Time Frame: End of procedure, approximately 45 minutes
Measured by the ability to record neural activity through DBS electrodes using circuitry developed at Duke for this purpose and/or a new implantable pulse generator (IPG; RC+S) developed by Medtronic. These intraoperative studies will specifically test a preliminary version of the RC+S that is not designed for implantation.
End of procedure, approximately 45 minutes

Secondary Outcome Measures

Secondary Outcome Measures

In a clinical study's protocol, a planned outcome measure that is not as important as the primary outcome measure for evaluating the effect of an intervention but is still of interest. Most clinical studies have more than one secondary outcome measure.
Outcome Measure
Measure Description
Time Frame
Number of Participants With Recorded DBS Local Evoked Potentials (DLEPs).
Time Frame: End of procedure, approximately 45 minutes
Measured by the ability to record DLEPs (changes in local electric field in response to DBS stimulation) through DBS electrodes using circuitry developed at Duke for this purpose and/or a new implantable pulse generator (IPG; RC+S) developed by Medtronic. These intraoperative studies will specifically test a preliminary version of the RC+S that is not designed for implantation. The DLEP recordings will be serially averaged with stimulus-triggering to remove random noise while preserving the evoked response.
End of procedure, approximately 45 minutes
Number of Participants With Recorded Spontaneous, Local Field Potentials (LFPs).
Time Frame: End of procedure, approximately 45 minutes
Measured by the ability to record LFPs (electrical activity in the local region of the DBS electrode) through DBS electrodes using circuitry developed at Duke for this purpose and/or a new implantable pulse generator (IPG; RC+S) developed by Medtronic. These intraoperative studies will specifically test a preliminary version of the RC+S that is not designed for implantation.
End of procedure, approximately 45 minutes

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Sponsor

The organization or person who initiates the study and who has authority and control over the study.
Dennis Turner, M.D.

Collaborators

Collaborators

An organization other than the sponsor that provides support for a clinical study. This support may include activities related to funding, design, implementation, data analysis, or reporting.
National Institute of Neurological Disorders and Stroke (NINDS)
National Institutes of Health (NIH)

Investigators

Investigators

A researcher involved in a clinical study. Related terms include site principal investigator, site sub-investigator, study chair, study director, and study principal investigator.
  • Principal Investigator: Dennis Turner, M.D., Duke University

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (ACTUAL)

Study Start

The actual date on which the first participant was enrolled in a clinical study. The "anticipated" study start date is the date that the researchers think will be the study start date.
April 5, 2018

Primary Completion (ACTUAL)

Primary Completion

The date on which the last participant in a clinical study was examined or received an intervention to collect final data for the primary outcome measure. Whether the clinical study ended according to the protocol or was terminated does not affect this date. For clinical studies with more than one primary outcome measure with different completion dates, this term refers to the date on which data collection is completed for all the primary outcome measures. The "anticipated" primary completion date is the date that the researchers think will be the primary completion date for the study.
March 26, 2019

Study Completion (ACTUAL)

Study Completion

The date on which the last participant in a clinical study was examined or received an intervention/treatment to collect final data for the primary outcome measures, secondary outcome measures, and adverse events (that is, the last participant's last visit). The "anticipated" study completion date is the date that the researchers think will be the study completion date.
March 26, 2019

Study Registration Dates

First Submitted

First Submitted

The date on which the study sponsor or investigator first submitted a study record to ClinicalTrials.gov. There is typically a delay of a few days between the first submitted date and the record's availability on ClinicalTrials.gov (the first posted date).
August 31, 2017

First Submitted That Met QC Criteria

First Submitted That Met QC Criteria

The date on which the study sponsor or investigator first submits a study record that is consistent with National Library of Medicine (NLM) quality control (QC) review criteria. The sponsor or investigator may need to revise and submit a study record one or more times before NLM's QC review criteria are met. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
August 31, 2017

First Posted (ACTUAL)

First Posted

The date on which the study record was first available on ClinicalTrials.gov after National Library of Medicine (NLM) quality control (QC) review has concluded. There is typically a delay of a few days between the date the study sponsor or investigator submitted the study record and the first posted date.
September 1, 2017

Study Record Updates

Last Update Posted (ACTUAL)

Last Update Posted

The most recent date on which changes to a study record were made available on ClinicalTrials.gov. There may be a delay between when the changes were submitted to ClinicalTrials.gov by the study's sponsor or investigator (the last update submitted date) and the last update posted date.
March 23, 2020

Last Update Submitted That Met QC Criteria

Last Update Submitted That Met QC Criteria

The most recent date on which the study sponsor or investigator submitted changes to a study record that are consistent with National Library of Medicine (NLM) quality control (QC) review criteria. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
March 6, 2020

Last Verified

Last Verified

The most recent date on which the study sponsor or investigator confirmed the information about a clinical study on ClinicalTrials.gov as accurate and current. If a study with a recruitment status of recruiting; not yet recruiting; or active, not recruiting has not been confirmed within the past 2 years, the study's recruitment status is shown as unknown.
March 1, 2020

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

Other Study ID Numbers

Identifiers or ID numbers other than the NCT number that are assigned to a clinical study by the study's sponsor, funders, or others. These numbers may include unique identifiers from other trial registries and National Institutes of Health grant numbers.
  • Pro00085076
  • UH3NS103468 (U.S. NIH Grant/Contract)

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

NO

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

Yes

product manufactured in and exported from the U.S.

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

Clinical Trials on Parkinson Disease

Clinical Trials on IPG; RC+S

Search Similar Trials

Sponsors and Collaborators

Medical Conditions

Drug Interventions

Conditions

Rare Diseases

Drug Interventions

Dietary Supplements

Sponsor/Collaborators

Locations

Cookie Settings

We use cookies to ensure that we give you the best experience on our website. For more details carefully read our Privacy and Cookies Policy. ...>>>You can change your preferences or withdraw your consent at any time by deleting the cookies from your website or computer as described in the policy. Please accept it and choose your preferences by ticking the corresponding boxes in the "Manage Settings" section below. Please carefully read our Terms of Service before you proceed with using any part of this website.
«Manage Settings