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Completed

NCT Number: NCT01738516

Contribution of High Resolution EEG Functional Connectivity Measures to Presurgical Evaluation of Patients With Intractable Epilepsy

Electroencephalography (EEG) with very high spatial resolution (HR-EEG, 256 electrodes) allow for better analysis of local and global activity of the cerebral cortex, as compared with conventional EEG. Since January 2012, the Neurology Department of CHU Rennes is the first clinical service in France equipped with such a system.

Applied to HR-EEG recordings, brain connectivity methods are likely to provide essential information (in the form of "connectivity graphs") on cortical networks, either dysfunctional or not, involved in the generation of interictal paroxysms (like spikes or spike-waves) and during seizures.

So far, many methods have been proposed (see for a review: Wendling et al., 2009; Wendling et al., 2010). However, since each method is highly sensitive to the type of model that is assumed for the underlying relationship between distinct brain regions (Ansari-Asl et al., 2006), none of them has yet demonstrated its effectiveness.

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Key information

Conditions

Epilepsy Brain Diseases Central Nervous System Diseases Nervous System Diseases

Age range

18 year and older

Sex eligibility

All sexes

Study type

Interventional

Phase

Not applicable

Primary location

Rennes University Hospital

Rennes, Brittany Region, 35033, France

Who can participate

Healthy volunteers accepted: Yes

Only the study team can determine whether someone qualifies for participation.

Inclusion criteria

Patients:

  • Being more than 18 years old,
  • Having a chronic partial epilepsy resistant to medical treatments well administered and well followed in the course of pre-surgical assessment.

Inclusion criteria

Healthy Volunteers:

  • Being French native speaker,
  • Being more than 18 years old,
  • Being right-handed.

Exclusion criteria

Patients:

  • All patients for whom a preoperative surgical exam is not suitable,
  • Any patient with psychiatric disease or intellectual disorder such that informed consent could not be obtained,
  • Any patient with no abnormal EEG during intercritical phases,
  • All patients presenting psychiatric, neuropsychological or developmental difficulties in addition to epilepsy,
  • Adult persons subject to legal protection (judicial protection, temporary guardianship/guardianship, administrative supervision), persons deprived of their liberty and pregnant or lactating women.

Exclusion criteria

Healthy Volunteers:

  • The presence of any psychiatric, neuropsychological, and developmental disorder,
  • Any uncorrected visual impairment,
  • Any trouble or delay in learning to read / speak or write French,
  • Being fully bilingual or multilingual
  • Medication, treatment and / or substances that may alter or modify brain functions,
  • Adult persons subject to legal protection (judicial protection, temporary guardianship/guardianship, administrative supervision), persons deprived of their liberty and pregnant or lactating women.

Treatment and study plan

electroencephalography

Procedure

Epileptic patients, as in healthy volunteers will be offered a review of EEG recording equipment resting on EEG-HR 256-channel EGI © in operation since January 2012 in the Van Gogh Service Unit of Neurology Rennes University Hospital (hospital Pontchaillou). The EEG is a routine now included in the Phase I report some epileptic patients during presurgical investigation. Patients to be included in this research protocol pass all review on the new device EEG-HR 256 channels. In addition to the rest condition, shared by both groups of participants, the healthy control subjects participate in two additional experimental tasks to be performed during recording. A picture naming task and a task of spelling words represented by these images.

Electroencephalography and additional experimental tasks

Procedure

Epileptic patients, as in healthy volunteers will be offered a review of EEG recording equipment resting on EEG-HR 256-channel EGI © in operation since January 2012 in the Van Gogh Service Unit of Neurology Rennes University Hospital (hospital Pontchaillou). The EEG is a routine now included in the Phase I report some epileptic patients during presurgical investigation. Patients to be included in this research protocol pass all review on the new device EEG-HR 256 channels. In addition to the rest condition, shared by both groups of participants, the healthy control subjects participate in two additional experimental tasks to be performed during recording. A picture naming task and a task of spelling words represented by these images.

Primary outcomes

  1. The quality of matching between i) the graphs produced by the evaluated connectivity method(s) applied to the HR-EEG and ii) the results of the visual analysis typically performed by an expert on the standard EEG recorded during intercritical phase.

    Time frame: 2 years

    Main objective :To determine which functional connectivity estimation method(s) show(s) best performance(s) for the identification of epileptogenic networks from the HR-EEG recording performed in epileptic patients.

Secondary outcomes

  1. The quality of matching between i) the connectivity graphs obtained from control subjects performing a well defined cognitive task to ii) data from the literature on networks activated and sustaining these cognitive processes.

    Time frame: 2 years

    Our secondary objectives are:

    • The application of linear, non-linear and phase synchronization methods in digital signal processing on broadband band analysis or on band-filtered EEG signals acquired during HR-EEG explorations of patients with epilepsy,
    • The evaluation of the performance of these methods by comparing the resulting connectivity graphs with those expected in healthy subjects (controls),
    • The application of the methods offering the best performances to data acquired in patients.

Sponsors and collaborators

Lead sponsor

Rennes University Hospital

Other

Registry information

Acronym: conneXion

Important dates

Study start
2013
Primary completion
2016
Study completion
2016
First posted
Nov 30, 2012
Registry last updated
May 24, 2023

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

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