Intracranial Stimulation Mapping for Epilepsy

Overseen By Matthew Maple

Age: 18+

Sex: Any

Trial Phase: Academic

Sponsor: University of Minnesota

Disqualifiers: Pregnancy, Cognitive impairment, others

No Placebo Group All trial participants will receive the active study treatment (no placebo)

Approved in 3 Jurisdictions This treatment is already approved in other countries

Compensation: Varies

Number of Visits: Unknown

Duration: Immediate

30 Participants Needed

Trial Summary

What is the purpose of this trial?

This is a single group prospective study to determine the feasibility for generating brain maps that localize cerebral functions and inter-regional information flow in partial epilepsy in adult patients.

Do I need to stop taking my current medications for the trial?

The trial information does not specify whether you need to stop taking your current medications. Please consult with the study team for guidance.

What data supports the effectiveness of the treatment Intracranial Stimulation Mapping for Epilepsy?

Electrical stimulation mapping (ESM) is considered the gold standard for identifying important brain areas and seizure zones in epilepsy surgery, helping to plan effective surgical treatments. Studies show that ESM, especially when combined with stereoelectroencephalography (SEEG), is crucial for successful surgical outcomes by accurately mapping brain functions and seizure origins. ^{1 2 3 4 5}

Is intracranial stimulation mapping safe for humans?

Intracranial stimulation mapping, used in epilepsy treatment, is generally considered safe, but there are potential safety concerns such as afterdischarges (brief electrical disturbances) and unwanted seizures that can occur during the procedure. ^{1 2 3 6 7}

How is Intracranial Stimulation Mapping different from other epilepsy treatments?

Intracranial Stimulation Mapping is unique because it uses electrical stimulation to precisely identify the areas of the brain responsible for seizures, which helps in planning surgery for epilepsy patients who do not respond to medication. Unlike other treatments, it provides detailed functional mapping of the brain, making it a critical tool for surgical planning. ^{1 2 3 5 7}

Research Team

Alexander Herman, MD

Principal Investigator

UMN

Eligibility Criteria

This trial is for adults over 18 with epilepsy who are already getting intracranial EEG monitoring at the University of Minnesota/MINCEP program. They must understand the study, agree to all procedures, and be available throughout. Pregnant individuals or those unable to make independent decisions due to cognitive impairments are excluded.

Inclusion Criteria

Stated willingness to comply with all study procedures and availability for the duration of the study

I am currently being monitored with an EEG at the University of Minnesota for epilepsy surgery.

I am 18 years old or older.

Exclusion Criteria

I am able to understand and make decisions about participating in this study.

Pregnancy ruled out prior to approval for intracranial EEG monitoring

Timeline

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

Treatment

Participants undergo intracranial stimulation mapping to generate brain maps for localizing cerebral functions and inter-regional information flow

Immediate

Multiple sessions (in-person)

Follow-up

Participants are monitored for safety and effectiveness after stimulation sessions

4 weeks

Treatment Details

Interventions

• Intracranial Stimulation Mapping

Trial Overview The study is testing a new way to create brain maps in adult patients with partial epilepsy. These maps aim to pinpoint where in the brain seizures start and how different regions communicate during a seizure.

Participant Groups

Group I: Research IESM Experimental Treatment 1 Intervention

Functional mapping for research application

Intracranial Stimulation Mapping is already approved in United States, European Union, Canada for the following indications:

Approved in United States as Intracranial Stimulation Mapping for:

• Epilepsy surgery planning
• Localization of cerebral functions
• Inter-regional information flow mapping

Approved in European Union as Electrical Stimulation Mapping (ESM) for:

• Pre-surgical evaluation for epilepsy
• Functional brain mapping

Approved in Canada as Cortical Stimulation Mapping for:

• Epilepsy surgery planning
• Brain function localization

Who Is Running the Clinical Trial?

University of Minnesota

Lead Sponsor

Trials

1,459

Recruited

1,623,000+

Findings from Research

In a study comparing 67 patients using stereoelectroencephalography (SEEG) and 106 patients using subdural electrodes (SDE), SEEG was found to have a higher likelihood of identifying sensory areas while maintaining comparable language and motor response evaluations.

SEEG demonstrated a lower incidence of afterdischarges (ADs) and unwanted electrical stimulation-induced seizures (EISs) compared to SDE, indicating that SEEG may offer superior safety and neurophysiologic validity for functional brain mapping.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Comparing electrical stimulation functional mapping with subdural electrodes and stereoelectroencephalography. Aungaroon, G., Vedala, K., Byars, AW., et al.[2023]

Electrical stimulation mapping (ESM) is crucial for locating the seizure onset zone in patients with medically resistant epilepsy, but there is currently no standardized protocol for its implementation.

The study proposes a unified ESM technique using specific parameters, such as a pulse width of 300 µs and stimulation currents of 1-6 mA for depth electrodes, to enhance the reliability of data across different medical centers.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Extraoperative electrical stimulation mapping in epilepsy presurgical evaluation: a proposal and review of the literature. Suller Marti, A., Mirsattari, SM., Steven, DA., et al.[2022]

Electrical stimulation mapping (ESM) using stereoelectroencephalography (SEEG) is crucial for accurately identifying seizure foci and eloquent brain areas, which is essential for effective surgical planning in epilepsy treatment.

SEEG stimulation has shown positive clinical outcomes in surgical interventions, and future applications may enhance functional mapping and cognitive investigations, potentially improving treatment strategies for epilepsy.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Stimulation Mapping Using Stereoelectroencephalography: Current and Future Directions. George, DD., Ojemann, SG., Drees, C., et al.[2020]

A survey of 56 epilepsy centers revealed significant variability in extraoperative electrical stimulation mapping (ESM) practices, including stimulation settings and language testing protocols, which could impact surgical outcomes.

Despite following their mapping procedures, 41% of centers reported persistent adverse language outcomes, highlighting the need for standardized guidelines to enhance the safety and efficacy of ESM in epilepsy surgery.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Extraoperative neurostimulation mapping: results from an international survey of epilepsy surgery programs. Hamberger, MJ., Williams, AC., Schevon, CA.[2021]

Effective connectivity analysis of intracranially recorded EEG during seizures can objectively localize the ictal-onset zone, showing promise as a reliable method alongside traditional visual analysis by epileptologists.

In a study of eight patients with refractory epilepsy, the electrode contact identified as having the highest connectivity consistently matched the ictal onset zone determined by visual analysis and was located within the resected brain region, indicating the method's accuracy.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Ictal-onset localization through connectivity analysis of intracranial EEG signals in patients with refractory epilepsy. van Mierlo, P., Carrette, E., Hallez, H., et al.[2013]

Electrical stimulation mapping is a crucial part of the surgical evaluation process in stereo-EEG (SEEG), helping to identify critical brain areas during epilepsy surgery.

The review highlights important differences between SEEG and electrocorticography techniques, emphasizing the need for clinicians to be aware of specific safety concerns and advantages when using electrical stimulation mapping in SEEG.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Electrical Stimulation Mapping With Stereo-EEG Electrodes. Britton, JW.[2018]

In a study of 10 patients with intractable epilepsy, intracerebral electrical stimulation (ES) resulted in 213 afterdischarges (ADs), with a higher incidence of ADs occurring from stimulation in the hippocampus compared to other brain areas.

While there was no significant correlation between the location of afterdischarges and the epileptogenic zone (EZ), the afterdischarges were more frequently localized to the irritative zone (IZ), suggesting that IZ may play a key role in the generation of ADs.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Properties of afterdischarges from electrical stimulation in patients with epilepsy. Liu, C., Yu, T., Ren, ZW., et al.[2018]

References

1. United States pubmed.ncbi.nlm.nih.gov

Comparing electrical stimulation functional mapping with subdural electrodes and stereoelectroencephalography. [2023]

2. Netherlands pubmed.ncbi.nlm.nih.gov

Extraoperative electrical stimulation mapping in epilepsy presurgical evaluation: a proposal and review of the literature. [2022]

3. Switzerland pubmed.ncbi.nlm.nih.gov

Stimulation Mapping Using Stereoelectroencephalography: Current and Future Directions. [2020]

4. United States pubmed.ncbi.nlm.nih.gov

Extraoperative neurostimulation mapping: results from an international survey of epilepsy surgery programs. [2021]

5. United States pubmed.ncbi.nlm.nih.gov

Ictal-onset localization through connectivity analysis of intracranial EEG signals in patients with refractory epilepsy. [2013]

6. United States pubmed.ncbi.nlm.nih.gov

Electrical Stimulation Mapping With Stereo-EEG Electrodes. [2018]

7. Netherlands pubmed.ncbi.nlm.nih.gov

Properties of afterdischarges from electrical stimulation in patients with epilepsy. [2018]