Acute Stimulation and Modulation of Stereotyped High-Frequency Oscillations

Official title

Acute Stimulation for the Modulation of Epileptic Events With a Closed-Loop Brain Interchange System in Drug Resistant Epilepsy

Overview

Overall, this study will investigate the functional utility of stereotyped HFOs by capturing them with a new implantable system (Brain Interchange - BIC of CorTec), which can sample neural data at higher rates \>=1kHz and deliver targeted electrical stimulation to achieve seizure control. In contrast to current closed-loop systems (RNS), which wait for the seizure to start before delivering stimulation, the BIC system will monitor the spatial topography and rate of stereotyped HFOs and deliver targeted stimulation to these HFO generating areas to prevent seizures from occurring. If the outcomes of our research in an acute setting become successful, the investigators will execute a clinical trial and run the developed methods with the implantable BIC system in a chronic ambulatory setting.

Detailed description

High-frequency oscillations (HFOs) of intracranial EEG (iEEG) have the potential to identify the surgical resection area/seizure onset zone (SOZ) in patients with drug-resistant epilepsy. However, multiple reports indicate that HFOs can be generated not only by epileptic cerebral tissue but also by non-epileptic sites often including eloquent regions such as motor, visual, and language cortices. In this project, the initial evidence of a recurrent waveform pattern is presented that may be sufficient to distinguish pathological HFOs from physiological ones. Specifically, the investigators show that the SOZ repeatedly generates sets of stereotypical HFOs with similar waveform morphology whereas the events recorded from out of SOZ were irregular. This morphological pattern served as a robust neurobiomarker to isolate SOZ from other brain areas in multiple patients consistently. While these promising preliminary results are in place, the functional utility of stereotyped HFOs in a closed-loop seizure control system remains unknown. As of today, not much is known whether the stereotyped HFOs generated by the SOZ can be detected with an implantable system. If this can be achieved, then HFOs can be strategically translated as a neurobiomarker into closed-loop seizure control applications. The investigators hypothesize that pathologic stereotyped HFOs can be captured with the implantable Brain Interchange (BIC) system of CorTec and spatial topography of these events can be utilized by the implantable system to deliver targeted electrical stimulation to achieve seizure control. Using an acute setup within the epilepsy monitoring unit (EMU), this project will investigate the feasibility of capturing stereotyped HFO events using the new BIC system and compare the detection results to those obtained with the commercially available amplifier (Aim-1). If the first phase (Aim-1) of the study becomes successful, later in the second phase (Aim-2), once again in the EMU, the investigators will deliver targeted electrical stimulation to those brain sites associated with stereotyped HFOs using the BIC.

During the entire study, the BIC system will not be implanted but used externally to assess the neural data through externalized electrodes and then deliver closed-loop stimulation. If the outcomes of the research in an acute setting become successful, the investigators will execute a clinical trial and run our methods with the implanted BIC system in a chronic ambulatory setting.

Interventions

• Device Brain Interchange System
  The CorTec Brain Interchange (BIC) is an implantable system with sensing and stimulation capability dedicated to promoting brain computer interface and closed-loop neuromodulation research. It is an externally powered implant which can provide neural data to a nearby computing station (communication unit connected to a personal computer) continuously. In return, computing station controls the implant e.g. for generating therapeutic electrical stimulation to the brain. It is expected that BIC wil

Primary outcome measures

• Feasibility of Detection of Stereotyped HFOs [Time frame: Within the first 3 years of the project]
• Feasibility of Delivering Closed-Loop Stimulation [Time frame: In the 4th and 5th years of the project]

Eligibility criteria

Inclusion criteria

• Patients with medically refractory epilepsy, who have been deemed appropriate candidates for intracranial EEG monitoring
• Adult men and women (18≤ age <70 years)
• Children (3≤ age <18 years)
• Includes women and minorities

Exclusion criteria

• Subjects will be excluded if their condition makes them unable to continue with recordings.

Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.

Healthy volunteers: No

Study design

Allocation

N/A

Model

Sequential

Masking

Open label

Primary purpose

Device feasibility

Study locations

United States · 2 centers

• Mayo Clinic — Rochester
• Baylor College of Medicine — Houston

Publications

• Ayyoubi AH, Fazli Besheli B, Quach MM, Gavvala JR, Goldman AM, Swamy CP, Bartoli E, Curry DJ, Sheth SA, Francis DJ, Ince NF. Benchmarking signal quality and spatiotemporal distribution of interictal spikes in prolonged human iEEG recordings using CorTec wireless brain interchange. Sci Rep. 2024 Feb 8;14(1):2652. doi: 10.1038/s41598-024-52487-5. PMID 38332136

Identifiers

NCT: NCT06898138 · 24-012951 · UH3NS117944

Primary sources (government registries)

• ClinicalTrials.gov (US NIH)

View this study on ClinicalTrials.gov ↗