Minimal Electrophysiology and Imaging Enhanced Deep Brain Stimulation (MIXT-DBS)

Minimal Electrophysiology and Imaging Enhanced Deep Brain Stimulation (MIXT-DBS)

The goal of this study is to learn if Deep Brain Stimulation (DBS) surgery can be streamlined for patients being treated for Parkinson's disease. The main questions it aims to answer are:

• Can a streamlined DBS surgery protocol with minimal electrophysiology and imaging (MiXT) safely replace the current use of intraoperative electrophysiology?
• Are we able to improve the efficiency, lower the invasiveness, and improve the clinical outcomes for patients undergoing DBS surgery?

Researchers will compare patients undergoing DBS surgery with this streamlined protocol to patients who previously underwent DBS surgery with the standard protocol to see if the accuracy, clinical outcomes, and efficiency improve.

Participants will undergo the standard protocol for DBS work-up and follow-up, but with minimal intraoperative electrophysiological testing.

Study Overview

• Status: Not yet recruiting
• Conditions: Parkinson Disease
• Intervention / Treatment: Procedure: Deep Brain Stimulation - Minimal Electrophysiology; Procedure: Deep Brain Stimulation - Standard

Detailed Description

In deep brain stimulation (DBS), accurate implantation of the stimulation electrode into the surgical target is crucial for a successful clinical outcome. The classic technique for surgical planning uses stereotactic atlases developed from a limited number of post-mortem samples. To better account for individual variability, imaging- and electrophysiology-based techniques have been developed. Electrophysiological techniques may offer intraoperative insight into anatomical positioning. Macrostimulation and microelectrode recording are gold-standards for simulating the therapeutic effects of stimulation during surgery, as well as predicting the threshold of stimulation-induced side effects. However, these techniques result in increased procedural time, reduced accuracy due to brain shift, and increased procedural risk due to the up to five electrode penetrations through brain tissue for testing. Motor evoked potentials (MEPs) deliver stimulation across the test and final implanted electrode to predict distance to the motor tract, and have been previously shown by our group to be an effective predictor of therapeutic threshold and side effects.

High-resolution magnetic resonance imaging (MRI) may be used to directly visualize target structures for individual patients, such as the subthalamic nucleus (STN), internal globus pallidus (GPi), and ventral intermediate nucleus of the thalamus (VIM). However, differentiating between the target and surrounding tissue is challenging for some surgical targets, and pre-surgical MRI may give imprecise coordinates of brain structures due to brain shift during surgery. Advances in machine learning have led to the development of software for assisting with detecting surgical targets from MRI images and for merging intraoperative images with the preoperative MRI images to represent the stereotactic space and verify the electrode position within the operating room setting.

Currently, our center uses MEPs, microelectrode recordings, and macrostimulation with software and intraoperative imaging plan and conduct DBS surgeries. Macrostimulation and microelectrode recordings may be redundant with the introduction of intraoperative MEP testing. This study aims to assess the safety, accuracy and clinical outcomes of using the streamlined procedure of MEP testing with imaging and assistive software only. This technique will be referred to as the MiXT technique.

• Study Type: Interventional
• Enrollment (Estimated): 80
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Lutz Weise, MD, PhD; Phone Number: 902-473-6850; Email: lutz.weise@nshealth.ca

Study Locations

• Canada
  • Nova Scotia
    • Halifax, Nova Scotia, Canada, B3H 3A7
      • Queen Elizabeth Health Science Centre

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Child; Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Patient qualifying for deep brain stimulation for the diagnosis of Parkinson's disease
• Informed consent

Exclusion Criteria:

• Lack of consent
• Electrical or other devices that preclude the performance of magnetic resonance imaging

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Non-Randomized
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Minimal Intraoperative Electrophysiology; Participants undergoing DBS for the diagnosis of Parkinson's disease	Procedure: Deep Brain Stimulation - Minimal Electrophysiology; Participants will undergo standard work-up and follow-up for DBS, but with minimal intraoperative electrophysiological testing.
Other: Standard Intraoperative Electrophysiology; Participants who previously underwent DBS surgery for the diagnosis of Parkinson's disease	Procedure: Deep Brain Stimulation - Standard; Participants underwent DBS surgery with standard intraoperative electrophysiological testing.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Accuracy of implanted electrode position	The distance between the final implanted electrode and the planned electrode, as measured on imaging software.	Intraoperative

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in disease score units on the Unified Parkinson's Disease Rating Scale	Assessment of therapeutic effects using the Unified Parkinson Disease Rating Scale	Baseline, 12 months
Change in disease score units on the Parkinsons Disease Questionnaire	Assessment of therapeutic effects using the Parkinsons Disease Questionnaire	Baseline, 12 months
Efficiency of Surgery	Assessment of operating room times and length of stay in hospital	Intraoperative
Intraoperative intensity of stimulation in milliampere	Intraoperative intensity of stimulation in milliamp, which elicits an activation of contralateral muscle groups (musculus interosseus dorsalis and the musculus tibialis anterior)	Intraoperative
Safety of streamlined protocol	Number of adverse events (neurological deficits, infections, hemorrhages), hardware complications (e.g. electrode dislocation and breakage), psychiatric side effects (e.g. depression, hypomania, obsessive behaviour), and unexpected stimulation induced side effects	4, 16, and 52 weeks post-surgery

Collaborators and Investigators

• Sponsor: Nova Scotia Health Authority
• Investigators: Principal Investigator: Lutz Weise, MD, PhD, Nova Scotia Health Authority

Study record dates

Study Major Dates

• Study Start (Estimated): October 1, 2025
• Primary Completion (Estimated): October 1, 2027
• Study Completion (Estimated): October 1, 2028

Study Registration Dates

• First Submitted: August 23, 2024
• First Submitted That Met QC Criteria: August 23, 2024
• First Posted (Actual): August 26, 2024

Study Record Updates

• Last Update Posted (Actual): March 25, 2025
• Last Update Submitted That Met QC Criteria: February 10, 2025
• Last Verified: February 1, 2025

More Information

Terms related to this study

• Keywords: Deep Brain Stimulation; Motor evoked potentials
• Additional Relevant MeSH Terms: Synucleinopathies; Brain Diseases; Central Nervous System Diseases; Nervous System Diseases; Neurodegenerative Diseases; Movement Disorders; Parkinsonian Disorders; Basal Ganglia Diseases; Parkinson Disease
• Other Study ID Numbers: MIXT-DBS

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: UNDECIDED

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No