Neuroimaging Evaluation in Neocortical Epilepsies

  • N. ColomboEmail author
  • N. Bargalló
  • D. Redaelli
Living reference work entry


Neocortical epilepsy is a chronic condition characterized by focal or generalized seizures starting within the cortex of any lobe of the brain. In this chapter, some of the most common epileptogenic lesions will be discussed, including malformations of cortical development (MCDs) comprising focal cortical dysplasia (FCD), polymicrogyria (PMG), heterotopia (HTP), hemimegalencephaly (HME), and acquired lesions after vascular and traumatic injuries that can develop to post-stroke epilepsy (PSE) or post-traumatic epilepsy (PTE). Some other lesions like cortical tubers of tuberous sclerosis complex and cavernous angioma, which can be associated to neocortical epilepsy, are treated in other chapters of this book. Clinical neuroradiology plays a pivotal role to establish the diagnosis and to select patient candidate to surgery. The radiological technique fundamental for neocortical epilepsies is brain magnetic resonance imaging (MRI). It is mandatory in patients with drug-resistant focal epilepsy (DRFE) aimed to detect the suspected associated anatomical lesion and to define its location, extension, and relationship with the eloquent brain areas.

An epilepsy-specific protocol is needed to identify even very subtle lesions, particularly tiny FCDs. Knowledge of the electro-clinical presentation is key for planning a correct MRI examination to use the proper sequence angulation. The MRI study should cover the whole brain including different weighted sequences in three planes. Interpretation should be performed by experienced readers and particularly focused on the brain area suspected as the epileptogenic zone (EZ). In non-lesional MRI patients, re-evaluation of MRI could be helpful after all ancillary tests are completed, including nuclear medicine and invasive electrophysiological investigation, such as stereo-electroencephalography (SEEG), to search retrospectively for subtle structural lesions.


Neocortical epilepsy Malformation of cortical development Focal cortical dysplasia Post-stroke epilepsy Post-traumatic epilepsy 

List of Abbreviations


18-Fluoro-2-deoxyglucose positron emission tomography


Drug-resistant focal epilepsy


Epileptogenic zone


Focal cortical dysplasia






Malformations of cortical development




Post-stroke epilepsy


Post-stroke seizures


Post-traumatic epilepsy


Post-traumatic seizures


Subtracted ictal SPECT co-registered to MRI


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Copyright information

© Springer International Publishing AG, part of Springer Nature 2018

Authors and Affiliations

  1. 1.Neuroradiology Department, Centro Regionale Chirurgia dell’Epilessia “Claudio Munari”ASST Grande Ospedale Metropolitano Niguarda Cà GrandaMilanoItaly
  2. 2.Magnetic Resonance Image Core Facility. Institut de Investigació Biomèdica August Pi I Sunyer (IDIBAPS)Image Diagnosis Center (CDIC). Hospital Clínic de BarcelonaBarcelonaSpain
  3. 3.Neuroimaging Laboratory Scientific Institute IRCCS Eugenio MedeaLeccoItaly

Section editors and affiliations

  • Nuria Bargalló
    • 1
    • 2
  1. 1.Image Diagnosis Center (CDIC)Hospital Clínic de BarcelonaBarcelonaSpain
  2. 2.Magnetic Resonance Image Core FacilityInstitut de Investigació Biomèdica August Pi I Sunyer (IDIBAPS)BarcelonaSpain

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