Investigation of Human Epileptic Networks by fMRI
Condition: Epilepsy
MeSH terms: Epilepsy
Study type: Interventional

Summary: 
      Background:

      In the Emilia-Romagna Region approximately 19.000 people are affected by epilepsy. About 25%
      of epileptic patients are drug-resistant (DRE) and some of them are eligible for resective
      surgery of the epileptogenic zone (EZ). The precise EZ localization is crucial for a good
      surgical outcome. Intracranial EEG (icEEG) recordings remain the gold-standard to localise
      the EZ. New neuroimaging techniques, like simultaneous recording of functional MRI and EEG
      (EEG-fMRI), with advanced methodological approaches as effective connectivity analysis (i.e.
      Dynamic Causal Modelling-DCM) might improve the EZ localization.

      Objectives:

      (1) To develop a non-invasive protocol for the investigation of the epileptic network in
      patients with surgically remediable epilepsies; (2) To shed light on the patho-physiological
      mechanisms of drug resistance in DRE; (3) To provide a validation of effective connectivity
      applied to fMRI data in epilepsy.

      Methods:

      Two Research Units (RU1, RU2) will identify and characterize a cohort of DRE patients
      eligible for resective surgery. RU1 will be in charge to perform the EEG/fMRI coregistration
      and data analysis. RU2 will be responsible for the surgical resection of epileptic foci.
      IcEEG recordings will be performed at the Claudio Munari Epilepsy Center, Ospedale Niguarda,
      Milano. RU1&RU2 will evaluate the fMRI data results and compare with icEEG findings or
      expert's surgical decision. The principle measures of outcome are: (a) percentage of
      concordance of fMRI results with icEEG findings or electro-clinical features in term
      epileptic network identification; (b) percentage of concordance between DCM findings and
      EZ/IZ localization; (c) percentage of concordance of DCM findings with icEEG or
      electro-clinical features regarding the causal hierarchy within the epileptic network.
    

Detailed description: 
      Background:

      About 25% of epileptic patients are drug-resistant (DRE) and some of them are eligible for
      resective surgery of the epileptogenic zone (EZ). The precise EZ localization is crucial for
      a good surgical outcome. Intracranial EEG (icEEG) recordings remain the gold-standard to
      localise the EZ. New neuroimaging techniques, like simultaneous recording of functional MRI
      and EEG (EEG-fMRI), with advanced methodological approaches as effective connectivity
      analysis (i.e. Dynamic Causal Modelling-DCM) might improve the EZ localization. This
      innovative tool will have the advantage to be non-invasive and safe with significant decrease
      of injuries, hospitalization, with a resulting favourable cost/benefit ratio.

      Objectives:

      (1) to provide a validation of effective connectivity applied to fMRI data in epilepsy. (2)To
      develop a non-invasive protocol for the investigation of the epileptic network in patients
      with surgically remediable epilepsies; (3) To shed light on the patho-physiological
      mechanisms of drug resistance in DRE.

      Methods:

      Two Research Units (RU1, RU2) will identify and characterize a cohort of DRE patients
      eligible for resective surgery. RU1 will perform patients' recruitment, presurgical
      evaluation and EEG/fMRI coregistration and data analysis. RU2 will perform patients'
      recruitment, presurgical evaluation and surgical resection of epileptic foci. IcEEG
      recordings will be performed at the Claudio Munari Epilepsy Center, Ospedale Niguarda, Milano
      . RU1&RU2 will evaluate the fMRI data results and compare with icEEG findings or expert's
      surgical decision. The principle measures of outcome are: (a) percentage of concordance of
      fMRI results with icEEG findings or electro-clinical features in term epileptic network
      identification; (b) percentage of concordance between DCM findings and EZ/IZ localization;
      (c) percentage of concordance of DCM findings with icEEG or electro-clinical features
      regarding the causal hierarchy within the epileptic network.
    

Intervention name(s): EEG/fMRI
Intervention type(s): Procedure
Intervention description(s): All the patients recruited will undergo to the following interventions:
1. Presurgical assesment protocol of the recruited patients (RU1 and RU2) that will includes: (a) detailed medical and epilepsy patients' history; (b) neurologic evaluation; (c) structural 3 Tesla MRI; (d) prolonged video-EEG monitoring including one-overnight EEG recording; (e) neuropsychological evaluation including quality of life evaluation. 2. EEG-fMRI coregistration: All subjects will undergo to a Video-EEG/fMRI study. This protocol will include a 32-channels EEG recorded simultaneously to fMRI data acquisition (3T scanner, Philips). This phase will be articulated in two steps: (i) acquisition of the EEG-fMRI data; (ii) fMRI data analysis (conventional and DCM analysis). RU1 will be charged for both steps. 3. Surgical resection of the epileptic foci and/or intracranial electrode recording (icEEG). The DRE patients in whom an intracranial recording will be considered unnecessary, will be operated at the RU2.
Intervention model: Single Group Assignment
Intervention model description: cohort prospectic, open, non randomized
Masking: None (Open Label)
Primary purpose: Diagnostic