Optimization of the Parameters of Vagal Nerve Stimulation (OPSTIMVAG)

Optimization of the Parameters of Vagal Nerve Stimulation in Pharmaco- Resistant Epileptic Patients Based on a Surface EEG Index of Functional Connectivity (PLI: Phase Lag Index): a Randomized Double-blind Multicenter Controlled Study.

Vagal nerve stimulation (VNS) is one of the neuromodulation techniques that can be indicated in patients suffering from refractory epilepsies, especially when an open resection has failed or is not indicated. However to date it is not possible to predict which patients will respond and what are the best parameters of stimulation to be set (pulse width, frequency and intensity). It has been shown that responders to VNS have reduced interictal cortical synchronicity on scalp EEG based on phase lag index (PLI), a marker of functional connectivity (Fc) The aim of this study is to test the following hypothesis: setting the parameters of stimulation on the basis of the lowest values of Phase Lag Index (PLI) obtained on scalp EEG with different settings of parameters (as compared with a randomly chosen set of commonly used parameters) will increase the rate of responders to VNS.

Study Overview

• Status: Active, not recruiting
• Conditions: Epilepsy
• Intervention / Treatment: Other: EEG; Other: Choice of VNS set of parameters based on the lowest PLI

• Study Type: Interventional
• Enrollment (Estimated): 140
• Phase: Not Applicable

Contacts and Locations

Study Locations

• France
  • FRA
    • Lyon, FRA, France, 69007
      • Hôpital St Joseph St Luc
  • France
    • Amiens, France, France, 80054
      • Department of functional explorations of the nervous system, CHU
    • Angers, France, France, 49933
      • Neuropediatrics department, CHU Angers
    • Bordeaux, France, France, 33000
      • Neurology Department, CHU Bordeaux
    • Dijon, France, France, 21079
      • Clinical neurophysiology, CHU Dijon
    • Grenoble, France, France, 38043
      • Epilepsy neurophysiopathology department, CHU Grenoble
    • Lille, France, France, 59037
      • Clinical neurophysiology, CHU Lille
    • Lyon, France, France, 69003
      • HCL Lyon
    • Marseille, France, France, 13885
      • Department of clinical neurophysiology, Hôpital La Timone, APHM
    • Nancy, France, France, 54000
      • Neurosurgery Department, CHRU Nancy
    • Nantes, France, France, 44093
      • Neurosurgery Department, CHU Nantes
    • Paris, France, France, 75013
      • Neurosurgery Department, APHP
    • Paris, France, France, 75014
      • Neurophysiology Department
    • Rennes, France, France, 35000
      • Epileptology Department, CHU Rennes
    • Rouen, France, France, 76000
      • Neurophysiology Department, CHU Rouen
    • Strasbourg, France, France, 67098
      • Neurology Department, CHU Strasbourg
    • Toulouse, France, France, 31059
      • Neurophysiological explorations, Hôpital Pierre Paul Riquet, Purpan
    • Tours, France, France, 37044
      • Neurology and clinical neurophysiology, CHU Bretonneau

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 12 years and older (Child, Adult, Older Adult)
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Male or female epileptic patients over 12 years of age
• Suffering from pharmaco-resistant epilepsy
• With newly implanted VNS Aspire SR device
• Surgery performed in the previous 6 months
• Electrode impedance should be within normal range ( < 4000 Ohms)
• Auto-stim mode working properly
• Mean number of seizures of at least (average 4 (mean value) / months during the baseline period)
• Patient, parents or legally representatives who have given written informed consent to allow the study data collection and procedures

Exclusion Criteria:

• Difficulty to read or understand the French language, or inability to understand the information regarding the study
• Total patient's IQ below 64
• Subject in exclusion period due to enrolment in another study
• Patient with postoperative left vocal cord paralysis
• Patient on VNS since more than 6 months

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Triple

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Sham Comparator: Control; VNS therapy with randomly-set combination of parameters (similar to current practice)	Other: EEG; Patient will have an EEG and 12 sets of parameters will be tested. EEG results will be analyzed which will allow to determine the set involving the lowest phase lag index.
Experimental: Experimental; VNS therapy with set combination of parameters chosen based on the lowest phase lag index	Other: EEG; Patient will have an EEG and 12 sets of parameters will be tested. EEG results will be analyzed which will allow to determine the set involving the lowest phase lag index.; Other: Choice of VNS set of parameters based on the lowest PLI; Vagal nerve stimulation according to PLI results.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Time Frame
Mean number of seizures per month	Change from baseline to 6 months
Mean number of seizures per month	Change from baseline to 12 months

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Score of depression	NDDI-E	Change from baseline to 12 months
Score of anxiety	GAD-7	Change from baseline to 12 months
Number of responders in each group		Change from baseline to 6 months
Number of responders in each group		Change from baseline to 12 months
Number of generalized seizures		Change from baseline to 6 months
Number of generalized seizures		Change from baseline to 12 months
Number of seizures with falls		Change from baseline to 6 months
Number of seizures with falls		Change from baseline to 12 months
Number of seizures with alteration of consciousness		Change from baseline to 6 months
Number of seizures with alteration of consciousness		Change from baseline to 12 months
Score of depression	NDDI-E	Change from baseline to 6 months
Score of anxiety	GAD-7	Change from baseline to 6 months
Score of quality of life	QUOLIE 31	Change from baseline to 6 months
Score of quality of life	QUOLIE 31	Change from baseline to 12 months

Collaborators and Investigators

• Sponsor: Assistance Publique Hopitaux De Marseille
• Investigators: Study Director: jean-olivier ARNAUD, Assistance Publique Hopitaux de Marseille

Study record dates

Study Major Dates

• Study Start (Actual): April 16, 2021
• Primary Completion (Actual): June 13, 2025
• Study Completion (Estimated): December 12, 2026

Study Registration Dates

• First Submitted: December 31, 2020
• First Submitted That Met QC Criteria: December 31, 2020
• First Posted (Actual): January 5, 2021

Study Record Updates

• Last Update Posted (Actual): February 10, 2026
• Last Update Submitted That Met QC Criteria: February 7, 2026
• Last Verified: February 1, 2026

More Information

Terms related to this study

• Keywords: epilepsy; vagal nerve stimulation; phase lag index
• Additional Relevant MeSH Terms: Brain Diseases; Central Nervous System Diseases; Nervous System Diseases; Epilepsy
• Other Study ID Numbers: 2020-05; 2020-A02657-32 (Other Identifier: ID-RCB)

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
• product manufactured in and exported from the U.S.: No