Evaluation of New Flexible High-density Intra-operative ECoG Electrodes for Epilepsy Surgery. ( EpiGrid ) (EpiGrid)

The EpiGrid Study Evaluation of New Flexible High-density Intra-operative ECoG Electrodes for Epilepsy Surgery

The objective of this prospective interventional monocentric clinical investigation is to evaluate the feasibility and performance of the flexible high-density SOFT ECoG electrode grids, manufactured by Neurosoft Bioelectronics SA (test device; TD), in comparison to regular high-density electrode grids (ADTech, CE-marked) (control device; CD) routinely used at the investigation site during epilepsy surgery.

Subjects will undergo ≥ 2 additional intracranial recordings pre- and post-resection with the TD next to the standard recordings with the CD during ECoG-tailored epilepsy surgery.

Study Overview

• Status: Recruiting
• Conditions: Focal Epilepsy; Intraoperative Monitoring
• Intervention / Treatment: Device: SOFT ECoG subdural grid electrode

• Study Type: Interventional
• Enrollment (Estimated): 12
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Karolina Janikowska Clinical Affairs Manager, PhD; Phone Number: 000 000-0000; Email: karolina.janikowska@neurosoft-bio.com
• Study Contact Backup: Name: G.J.M. Zijlmans Study Principal Investigator, PhD; Phone Number: 000 000-0000; Email: G.J.M.Zijlmans@umcutrecht.nl

Study Locations

• Netherlands
  • Utrecht, Netherlands, 3584CX
    • Recruiting
    • University Medical Center (UMC) Utrecht
    • Principal Investigator: Dr. G.J.M. (Maeike) Zijlmans Prof. Dr.
    • Contact: Maryse van 't Klooster Study Coordinator, PhD

Participation Criteria

Eligibility Criteria

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

Description

Inclusion Criteria:

• Age ≥18 years at the time of enrolment
• Lesional epilepsy (incl. secondary mesial temporal sclerosis) that is considered a candidate for intra-operative high-density grid recordings (incl. patients who underwent sEEG preceding resective surgery)
• Provided informed consent for study participation by the subject

Exclusion Criteria:

• Occipital lesion
• Surgeries involving a primary mesial temporal lesion, a disconnection, or hemispherectomy.
• Planned ioECoG recordings during fully awake surgery and/or functional recordings
• Use of anticoagulants that cannot be discontinued during the perioperative period, or a factor XIII deficiency or any other haematological disease
• Active participation in another investigational device study
• Any other condition that in the opinion of the investigator may adversely affect the safety of the subject or would limit the subject's ability to complete the study.
• Insufficient understanding of Dutch language.

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: All subjects

Device: SOFT ECoG subdural grid electrode; Test Device (SOFT ECoG subdural grid electrode): used for recording. During epilepsy surgery, in addition to standard clinical protocol (recording with comparator device), subjects will undergo ≥ 2 additional intracranial recordings with the SOFT ECoG flexible high density electrode grid (TD). Recording will be registered pre- and post-resection. All procedures will be conducted according to standard clinical practice. Any medical decision making will be done using the standard of care CE-marked device (CD). The investigational, non-CE marked device is not used for clinical decision making.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Background SNR pre-resection recording	Performance in terms of signal quality is assessed via background signal to noise ratio (SNR). Only channels which record properly based on visual inspection (no noise, no flat line) will be included in the background SNR calculation. For the pre-resection recordings (SITUATION I/I*), the background SNR per (included) channel and the average SNR for the electrode grid will be calculated, and pairwise comparison will be conducted between TD (SITUATION I*) and CD (SITUATION I).	up to 24 hours

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Electrode deficiency ratio (%)	The individual electrodes will be classified, per recording, as poor or good signal quality based on visual criteria (i.e., noise, flat signal due to overlap with resection cavity or silicone of secondary electrode strip, pulsation artifacts). As a result, an electrode deficiency ratio (%) will be calculated as follows: # bad electrodes divided by the total # of electrodes per recording. This will be determined for the similar positioned CD recording (SITUATION I/II) to allow comparison with the TD (SITUATION I*/I**).	up to 24 hours
Epileptic biomarker identification ( eg. number of spikes/HFOs per min, event SNR)	After the surgery, spikes and high frequency oscilations (HFOs) will be visually marked in the final minute of the recording (note: assisted by automated spike/HFO detector) and checked by an expert. Marking of spikes and HFOs will be done in the TD and the corresponding CD recordings pre- and post-resection. Event rates (number of spikes/HFOs per minute) per channel and total per recording will be compared between the TD and CD. The average event SNR per channel and the average SNR per epileptogenic event type will be calculated per recording. The event SNR will be compared between the CD recording (SITUATION I/II) and the TD (SITUATION I*/I**).	up to 24 hours
Background SNR of post-resection recordings	The background SNR for post-resection recordings (SITUATION II/II**) will be computed and pairwise compared. Note that it shall be considered that for the post-resection recordings (SITUATION II/II**), in particular when measuring near/in the resection cavity, the performance of both the TD and CD for electrode deficiencies might differ significantly, positively and negatively.	up to 24 hours
Surgical complications (e.g. SAEs/SADEs)	The safety analysis will include surgical complications in terms of device deficiencies (DDs) and serious adverse events (SAEs), and whether these are device related (SADEs).	up to hospital discharge, on average at 10 days
Usability evaluation	A (digital) usability questionnaire (system usability scale + open questions) will be collected (within 48h after surgery).	up to 48 hours

Collaborators and Investigators

• Sponsor: Neurosoft Bioelectronics SA
• Collaborators: UMC Utrecht; European Research Council

Study record dates

Study Major Dates

• Study Start (Actual): January 1, 2025
• Primary Completion (Estimated): March 1, 2027
• Study Completion (Estimated): March 1, 2027

Study Registration Dates

• First Submitted: December 19, 2023
• First Submitted That Met QC Criteria: January 3, 2024
• First Posted (Actual): January 12, 2024

Study Record Updates

• Last Update Posted (Actual): December 10, 2025
• Last Update Submitted That Met QC Criteria: December 9, 2025
• Last Verified: December 1, 2025

More Information

Terms related to this study

• Keywords: HFO; epilepsy surgery; intra-operative electrocorticography; epileptic biomarkers; high frequency oscillations; flexible ECoG; subdural electrode
• Additional Relevant MeSH Terms: Brain Diseases; Central Nervous System Diseases; Nervous System Diseases; Epilepsy; Epilepsies, Partial
• Other Study ID Numbers: CIP-01202

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: No