Trial Outcomes & Findings for Microelectrodes in Epilepsy (NCT NCT05200455)

NCT ID: NCT05200455

Last Updated: 2022-09-07

Results Overview

With the occipito-temporal implantation approach of implantation of microelectrodes, feasibility will measured by the number of place responsive neurons that could be isolated.

• Recruitment status: COMPLETED
• Study phase: NA
• Target enrollment: 34 participants
• Primary outcome timeframe: Evaluated for each patient during monitoring period of approximately 2 weeks
• Results posted on: 2022-09-07

Participant Flow

Participant milestones

Measure	Microelectrodes Patients who qualify for this study were implanted with standard electrodes that in addition have microelectrodes embedded in the standard macroelectrodes that are standard of care in epilepsy surgery. Microelectrodes have been shown to record single unit potentials and more localized field potentials on EEG recordings. There is no control group as patient serve as their own control. The patient is presented with a cognitive task and signals are recorded during the cognitive task, the signals during the different elements of the cognitive task are compared to each other or compared to a baseline state. There is no therapeutic intervention tested, the study is aimed to understand cognitive memory processing and translate animal studies to humans that have described successful memory encoding with certain EEG signals (place cells, theta oscillations)
Overall Study STARTED	34
Overall Study COMPLETED	30
Overall Study NOT COMPLETED	4

Reasons for withdrawal

Measure

Microelectrodes Patients who qualify for this study were implanted with standard electrodes that in addition have microelectrodes embedded in the standard macroelectrodes that are standard of care in epilepsy surgery. Microelectrodes have been shown to record single unit potentials and more localized field potentials on EEG recordings. There is no control group as patient serve as their own control. The patient is presented with a cognitive task and signals are recorded during the cognitive task, the signals during the different elements of the cognitive task are compared to each other or compared to a baseline state. There is no therapeutic intervention tested, the study is aimed to understand cognitive memory processing and translate animal studies to humans that have described successful memory encoding with certain EEG signals (place cells, theta oscillations)

Overall Study These patients were not implanted with intracranial electrodes for clinical reasons .

4

Baseline Characteristics

Microelectrodes in Epilepsy

Baseline characteristics by cohort

Measure	Microelectrodes n=34 Participants Patients who qualify for this study will be implanted with standard electrodes as well as microelectrodes for their intracranial seizure monitoring. Microelectrodes: Microelectrode implantation
Age, Categorical <=18 years	0 Participants n=5 Participants
Age, Categorical Between 18 and 65 years	34 Participants n=5 Participants
Age, Categorical >=65 years	0 Participants n=5 Participants
Sex/Gender, Customized	34 Participants n=5 Participants
Sex: Female, Male Female	17 Participants n=5 Participants
Sex: Female, Male Male	17 Participants n=5 Participants
Race (NIH/OMB) American Indian or Alaska Native	0 Participants n=5 Participants
Race (NIH/OMB) Asian	0 Participants n=5 Participants
Race (NIH/OMB) Native Hawaiian or Other Pacific Islander	0 Participants n=5 Participants
Race (NIH/OMB) Black or African American	0 Participants n=5 Participants
Race (NIH/OMB) White	33 Participants n=5 Participants
Race (NIH/OMB) More than one race	0 Participants n=5 Participants
Race (NIH/OMB) Unknown or Not Reported	1 Participants n=5 Participants

PRIMARY outcome

Timeframe: Evaluated for each patient during monitoring period of approximately 2 weeks

Population: Participants included patients undergoing intra-cranial EEG monitoring for TLE and are implanted with depth electrodes and microelectrodes via the trans-occipital approach. The total number of place responsive neurons recorded from all participants is reported below.

With the occipito-temporal implantation approach of implantation of microelectrodes, feasibility will measured by the number of place responsive neurons that could be isolated.

Outcome measures

Measure	Microelectrodes n=30 Participants Patients who qualify for this study will be implanted with standard electrodes as well as microelectrodes for their intracranial seizure monitoring. Microelectrodes: Microelectrode implantation
Feasibility of Microelectrode Technology to Isolate Place Responsive Neurons in the Human Hippocampus as Measured by the Number of Place Responsive Neurons.	79 place responsive neurons

SECONDARY outcome

Timeframe: Evaluated for each patient during monitoring period of approximately 2 weeks

Population: Participants included patients undergoing intra-cranial EEG monitoring for TLE and are implanted with depth electrodes and microelectrodes.

Secondary objective is to investigate whether it is possible to predict the speed of which each participant is performing and navigating during the cognitive task via the intracranial spectral EEG changes (alpha, beta, delta, theta, gamma, and high-gamma) during these tasks. Accuracy of frequency band (brain waves) predicting speed during specific cognitive tasks is measured by how precisely the frequency band predicts navigational speed and is expressed as a percentage of correct prediction.

Outcome measures

Measure	Microelectrodes n=30 Participants Patients who qualify for this study will be implanted with standard electrodes as well as microelectrodes for their intracranial seizure monitoring. Microelectrodes: Microelectrode implantation
How Precise the Frequencies (Alpha, Beta, Delta, Theta, Gamma, and High-gamma) of Neural Brain Activity Predict the Speed of the Participant at Performing the Cognitive Task (Accuracy Measured in Percentage). Delta	0.477 percentage of accuracy in decimals Interval 0.4 to 0.492
How Precise the Frequencies (Alpha, Beta, Delta, Theta, Gamma, and High-gamma) of Neural Brain Activity Predict the Speed of the Participant at Performing the Cognitive Task (Accuracy Measured in Percentage). Theta	0.490 percentage of accuracy in decimals Interval 0.449 to 0.499
How Precise the Frequencies (Alpha, Beta, Delta, Theta, Gamma, and High-gamma) of Neural Brain Activity Predict the Speed of the Participant at Performing the Cognitive Task (Accuracy Measured in Percentage). High-gamma	0.382 percentage of accuracy in decimals Interval 0.305 to 0.405
How Precise the Frequencies (Alpha, Beta, Delta, Theta, Gamma, and High-gamma) of Neural Brain Activity Predict the Speed of the Participant at Performing the Cognitive Task (Accuracy Measured in Percentage). Alpha	0.440 percentage of accuracy in decimals Interval 0.372 to 0.477
How Precise the Frequencies (Alpha, Beta, Delta, Theta, Gamma, and High-gamma) of Neural Brain Activity Predict the Speed of the Participant at Performing the Cognitive Task (Accuracy Measured in Percentage). Beta	0.444 percentage of accuracy in decimals Interval 0.388 to 0.537
How Precise the Frequencies (Alpha, Beta, Delta, Theta, Gamma, and High-gamma) of Neural Brain Activity Predict the Speed of the Participant at Performing the Cognitive Task (Accuracy Measured in Percentage). Gamma	0.362 percentage of accuracy in decimals Interval 0.29 to 0.419

Adverse Events

Microelectrodes

Serious events: 2 serious events

Other events: 0 other events

Deaths: 0 deaths

Serious adverse events

Measure	Microelectrodes n=30 participants at risk Patients who qualify for this study will be implanted with standard electrodes as well as microelectrodes for their intracranial seizure monitoring. Microelectrodes: Microelectrode implantation
Infections and infestations Infection	3.3% 1/30 • Number of events 1 • Evaluated for each patient during monitoring period of approximately 2 weeks
Infections and infestations Chronic Inflammatory Reaction	3.3% 1/30 • Number of events 1 • Evaluated for each patient during monitoring period of approximately 2 weeks

Other adverse events

Adverse event data not reported

Additional Information

Dr. Barbara Jobst

Dartmouth-Hitchcock Medical Center

Phone: 6036505000

Email: Barbara.C.Jobst@hitchcock.org

Results disclosure agreements

• Principal investigator is a sponsor employee
• Publication restrictions are in place