Presurgical Motor Mapping With Transcranial Magnetic Stimulation (TMS)

Validation of Presurgical Motor Mapping With Transcranial Magnetic Stimulation (TMS) in Patients With Epilepsy

The aim of the study is to examine the degree of concordance between presurgical neuronavigation guided TMS (nTMS) and direct cortical stimulation (DCS) in identifying hand motor cortex in adults undergoing epilepsy surgery.

Navigated transcranial magnet stimulation (nTMS), MagStim RapidStim2 Magnetic stimulation will be delivered to hand primary motor cortex, with positive and negative functional sites determined through surface electromyography (EMG).

The study will involve patients ages 12-60 years, with planned neurosurgery involving implantation of intracranial subdural electrodes including over the precentral gyrus.

Navigated transcranial magnet stimulation (nTMS), MagStim RapidStim2 Magnetic stimulation will be delivered to hand primary motor cortex, with positive and negative functional sites determined through surface electromyography (EMG).

The primary outcome measure will be spatial correlation between topographic maps of hand motor representation obtained through nTMS compared to direct, extra-operative cortical stimulation performed as part of routine clinical care. A secondary outcome measure will be safety and tolerability of TMS in the epilepsy patients.

Study Overview

• Status: Completed
• Conditions: Epilepsy
• Intervention / Treatment: Device: The Magstim Rapid2,

Detailed Description

This study will be an open-label feasibility study which applies nTMS to subjects with incoming epilepsy surgery and pre-surgical motor mapping. No study-related medication changes are expected -- participants will remain compliant with their regular anticonvulsant regimen throughout each study phase. All patients will have undergone a complete history and neurological exam as part of their routine clinical care at the New York University (NYU) Comprehensive Epilepsy Center.

Fourteen (14) patients will undergo epilepsy surgery with expected subdural grid coverage over primary motor cortex. Potential subjects will be identified at the weekly multi-disciplinary epilepsy conference. Subjects must have a recent (<2 years) MRI scan, and registration of the TMS coil to the MRI scan via the Brainsight neuronavigation system will be utilized to guide TMS coil placement (Gugino et al 2001). When a presurgical fMRI (functional magnetic resonance imaging) is available which demonstrates the patient's hand knob, the fMRI will be used with the Brainsight neuronavigation system. Subjects will be recruited and consented during a presurgical clinical visit where the patient's primary epileptologist will introduce members of the research team.

nTMS mapping

Patients will receive a session of single-pulse TMS mapping of the motor area, at the outpatient TMS clinic at NYU Neurology Ambulatory Care Center, at 240 E 38th St 20th Floor prior their epilepsy surgery according to the following procedures:

1. Determination of the motor threshold by (1) finding the most excitable region in the hand knob which elicits the strongest compound muscle action potential (CMAP) in the APB muscle; (2) finding the motor threshold by determining output stimulation intensity which generates peak to peak CMAP response above 50 mV (Millivolts) in 5/10 stimulation cycles (Rossini et al., 1994).
2. Concurrent EMG will be measured with electrodes placed at APB (abductor policis brevis atrial premature beat), abductor digiti minimi, flexor carpiradialis muscles. Reference electrode will be placed at the ipsilateral elbow above the brachial biceps muscle.
3. Mapping of the upper extremity. After determination of the MT (motor threshold), mapping of the UE(Upper Extremity) will be performed at 110% of the rMT (resting motor threshold). All positive and negative stimulation sites will be recorded and saved. Patients will be closely monitored during TMS stimulation. Each subject will have a complete neurological examined by a neurologist before and immediately after nTMS. Patients will also be provided a side effects questionnaire after TMS mapping. Patients will then be asked to keep a 7 day seizure diary after the nTMS session.

After epilepsy surgery patients will receive the standard care for post-operative patients which including close monitoring in ICU overnight. Patients will be transferred to the floor for further clinical evaluation before discharge. Clinical outcome will be evaluated in the post-operative clinic visit within 1 month after discharge. The value of a clinical follow up is to evaluate for any discrepancy between nTMS and DCS, to determine which modality better predicts functional outcome. Any seizure recurrence or neurological deficit will be recorded at the follow-up clinical visit.

The trial is designed to detect strength of spatial correlation between topographic maps of hand motor representation obtained through noninvasive nTMS compared to direct, extra-operative cortical stimulation obtained as part of usual clinical evaluation during epilepsy surgery, as measured by (a) average distance between positive motor mapping sites of DCS compared to nTMS and (b) degree of concordance between positive and negative motor mapping sites between DCS and nTMS, to generate positive and negative predictive values, and (c) average distance between positive motor functional sites of fMRI compared to nTMS.

• Study Type: Interventional
• Enrollment (Actual): 2
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United States
  • New York
    • New York, New York, United States, 10016
      • New York University Langone Medical Center

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 12 years to 60 years (Child, Adult)
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• 12-60 years of age
• Planned neurosurgery involving implantation subdural electrodes over the precentral gyrus

Exclusion Criteria:

• Inability to sign informed consent .
• Hemiparesis worse than 4-/5 on the side contra lateral to the planned implant
• Inability to get an MRI, or MRI older than 2 years
• Frequent (>1 per day) motor seizures
• Prior neurosurgery
• Metal in the head, including shrapnel
• Implanted stimulation devices, including DBS (Deep Brain Stimulator), RNS (Responsive Neurostimulator), VNS (Vagus Nerve Stimulator), PPM (Permanent Pacemaker)
• Pregnancy
• Use of a medication known to increase the risk of seizures, including certain antipsychotics (clozapine), bronchodilators (aminophylline, theophylline), immunomodulatory agents (cyclosporine), and antibiotics (penicillins, cephalosporins, amphotericin, imipenem)

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Diagnostic
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: nTMS; Patients will receive a single-pulse TMS mapping of the motor area for the following reasons to determine the motor threshold, measure concurrent EMG, and mapping of the upper extremity.	Device: The Magstim Rapid2,; Transcranial Magnetic Stimulation, which is a microprocessor-controlled machine which delivers both single and repetitive transcranial magnetic stimulation (TMS). single and repetitive transcranial magnetic stimulation (TMS). TMS will be applied as single pulses to determine motor evoked potentials (MEPs), there will be no modulation of cortical excitability.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Time Frame
Average Distance Between Positive Motor Mapping Sites of DCS	30 minutes
Average Distance Between Positive Motor Mapping Sites of nTMS	30 minutes
Average Distance Between Positive Motor Functional Sites of fMRI	30 minutes
Average Distance Between Positive Motor Functional Sites of nTMS	30 minutes

Collaborators and Investigators

• Sponsor: NYU Langone Health
• Investigators: Principal Investigator: Anli Liu, MD, MA, NYU Langone Health

Study record dates

Study Major Dates

• Study Start (Actual): September 10, 2016
• Primary Completion (Actual): November 17, 2016
• Study Completion (Actual): February 23, 2023

Study Registration Dates

• First Submitted: April 8, 2016
• First Submitted That Met QC Criteria: April 13, 2016
• First Posted (Estimated): April 18, 2016

Study Record Updates

• Last Update Posted (Estimated): November 14, 2023
• Last Update Submitted That Met QC Criteria: October 27, 2023
• Last Verified: October 1, 2023

More Information

Terms related to this study

• Keywords: EMG; Electromyography; Transcranial magnet stimulation (nTMS); Brainsight Neuronavigation
• Additional Relevant MeSH Terms: Brain Diseases; Central Nervous System Diseases; Nervous System Diseases; Epilepsy
• Other Study ID Numbers: 15-00176

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