title: Assessment and surgical outcomes for mild type I and severe type II cortical dysplasia: a critical review and the UCLA experience.
abstract: Recent findings on the clinical, electroencephalography (EEG), neuroimaging, and surgical outcomes are reviewed comparing patients with Palmini type I (mild) and type II (severe) cortical dysplasia. Resources include peer-reviewed studies on surgically treated patients and a subanalysis of the 2004 International League Against Epilepsy (ILAE) Survey of Pediatric Epilepsy Surgery. These sources were supplemented with data from University of California, Los Angeles (UCLA). Cortical dysplasia is the most frequent histopathologic substrate in children, and the second most common etiology in adult epilepsy surgery patients. Cortical dysplasia patients present with seizures at an earlier age than other surgically treated etiologies, and 33-50% have nonlocalized scalp EEG and normal magnetic resonance imaging (MRI) scans. 2-((18)F)Fluoro-2-deoxy-D-glucose positron emission tomography (FDG-PET) is positive in 75-90% of cases. After complete resection, 80% of patients are seizure free compared with 20% with incomplete resections. Compared with type I, patients with type II cortical dysplasia present at younger ages, have higher seizure frequencies, and are extratemporal. Type I dysplasia is found more often in adult patients in the temporal lobe and is often MRI negative. These findings identify characteristics of patients with mild and severe cortical dysplasia that define surgically treated epilepsy syndromes. The authors discuss future challenges to identifying and treating medically refractory epilepsy patients with cortical dysplasia.
authors.affiliation: Department of Pediatric Neurology, University of California, Los Angeles, California, USA.
authors.forename: Jason T
authors.initials: JT
authors.lastname: Lerner
authors.forename: Noriko
authors.initials: N
authors.lastname: Salamon
authors.forename: Jason S
authors.initials: JS
authors.lastname: Hauptman
authors.forename: Tonicarlo R
authors.initials: TR
authors.lastname: Velasco
authors.forename: Marta
authors.initials: M
authors.lastname: Hemb
authors.forename: Joyce Y
authors.initials: JY
authors.lastname: Wu
authors.forename: Raman
authors.initials: R
authors.lastname: Sankar
authors.forename: W
authors.initials: W
authors.lastname: Donald Shields
authors.forename: Jerome
authors.initials: J
authors.lastname: Engel
authors.forename: Itzhak
authors.initials: I
authors.lastname: Fried
authors.forename: Carlos
authors.initials: C
authors.lastname: Cepeda
authors.forename: Veronique M
authors.initials: VM
authors.lastname: Andre
authors.forename: Michael S
authors.initials: MS
authors.lastname: Levine
authors.forename: Hajime
authors.initials: H
authors.lastname: Miyata
authors.forename: William H
authors.initials: WH
authors.lastname: Yong
authors.forename: Harry V
authors.initials: HV
authors.lastname: Vinters
authors.forename: Gary W
authors.initials: GW
authors.lastname: Mathern
mesh_terms: D003863:Depression / Q000209:etiology; D004827:Epilepsy / Q000145:classification / Q000209:etiology* / Q000601:surgery*; D007839:Functional Laterality; D006801:Humans; D054220:Malformations of Cortical Development / Q000145:classification / Q000150:complications / Q000601:surgery; D017063:Outcome Assessment, Health Care