Investigation of Human Epileptic Networks by fMRI
- Conditions
- Epilepsy
- Registration Number
- NCT03582345
- Lead Sponsor
- Azienda Unita' Sanitaria Locale Di Modena
- Brief 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.
Recruitment & Eligibility
- Status
- COMPLETED
- Sex
- All
- Target Recruitment
- 35
- Adults patients (≥18yrs) diagnosed with DRE (drug-resistant epilepsy), candidate for epilepsy surgery who will undergo directly to the resection of the epileptic focus or to icEEG recordings for a better EZ definition
- Patients with idiopathic generalized epilepsies;
- Patients with focal epilepsy responders to AED;
- Patients with refractory focal epilepsy but contraindicated to perform a MRI;
- Patients who refute to have the EEG-fMRI;
- Patients whose cognitive status is too impaired to complete the necessary study forms.
Study & Design
- Study Type
- INTERVENTIONAL
- Study Design
- SINGLE_GROUP
- Primary Outcome Measures
Name Time Method Epilectic network months 3-18 The non-invasive EEG-fMRI (conventional analysis) study will reveal the epileptic network in more than 80% of the DRE patients recruited.
Causal hierarchy within the epileptogenic network months 3-18 DCM based on fMRI will identified the causal hierarchy within the epileptogenic network in more than 80% of the patients studied. Particularly the following outcome measures will be considered: (a) localization of epileptogenic zone (EZ); (b) localization of irritative zone (IZ).
Drug-resistance months 3-18 Identification of possible mechanisms of drug-resistance in refractory epilepsies The outcome measure system relies on: (a) clinical data collection recorded in an electronic dedicated case report form (CRF), (b) the qualitative results of EEG-fMRI recordings. Particularly the level of concordance between fMRI maps and icEEG/ expert's surgical decision will be assessed by looking the distance (in cm) between the area of maximum BOLD changes (Global Maxima) and the defined EZ, as already validated by others; (c) surgical outcome (at 3-6-9-12 months after surgery) in those DRE patients operated as measure of the DCM success.
- Secondary Outcome Measures
Name Time Method