Modern techniques of epileptic focus localization

Area of Science:

• Neurology
• Neurosurgery
• Medical Imaging

Background:

• Understanding epileptic zones is vital for presurgical evaluation and resection planning in refractory epilepsy.
• The network concept highlights that epileptic zones involve complex interactions between multiple brain structures.
• This network understanding is crucial for comprehending partial epilepsy pathophysiology and guiding surgical decisions.

Purpose of the Study:

• To review advanced imaging techniques for mapping epileptic zones.
• To explore how these techniques reveal the structural and functional organization of epileptic networks.
• To assess the impact of these advancements on epilepsy surgery candidacy.

Main Methods:

• Magnetic resonance (MR) postprocessing for improved detection of epileptogenic lesions.
• Single photon emission computed tomography (SPECT) for seizure-onset zone localization.
• Positron emission tomography (PET) for functional deficit zone assessment (hypometabolism).
• Functional magnetic resonance imaging (fMRI) to detect hemodynamic fluctuations for irritative zone localization.

Main Results:

• Advanced MR techniques enhance the accuracy of identifying epileptogenic lesions.
• SPECT and PET imaging effectively localize seizure-onset and functional deficit zones, respectively.
• Novel fMRI methods accurately map the irritative zone by detecting interictal epileptiform discharge-related hemodynamic changes.

Conclusions:

• Advanced neuroimaging techniques provide comprehensive mapping of epileptic zones and their networks.
• These techniques improve the understanding and localization of epilepsy-related brain regions.
• The findings expand surgical treatment options for epilepsy patients previously deemed unsuitable.