title: Seizure outcome after surgery for epilepsy due to malformation of cortical development.
abstract: OBJECTIVE
  To explore seizure outcome after surgery for focal epilepsy due to malformation of cortical development (MCD), with focus on the role of MRI.
  
  
  METHODS
  Thirty-five patients who had surgery for intractable focal epilepsy due to MCD identified by preoperative MRI and confirmed by histopathologic analysis of resected tissue were studied. Patients were aged 3 months to 47 years (median, 14 years) at the time of surgery. Duration of follow-up was 1 to 7.9 (mean, 3.4) years.
  
  
  RESULTS
  At latest follow-up, 17 patients (49%) had Engel Class I outcome with no seizures or auras only; eight patients (23%) had Class II outcome, with rare disabling seizures; seven patients (20%) had worthwhile improvement; and three patients (9%) had no improvement. Seizure-free outcome tended to be more frequent among patients who had complete resection of unilateral MCD (excluding hemimegalencephaly) based on postoperative MRI (7/12; 58%), compared with patients with unilateral MCD who had incomplete resection (3/11; 27%), but the difference was not significant. The frequency of seizure-free outcome did not differ significantly between children (8/14; 57%), adolescents (7/15; 47%) or adults (2/6; 33%); between patients who had daily (12/24; 50%), weekly (4/9; 44%), or monthly (1/2; 50%) seizures preoperatively; between patients who had temporal (2/6; 33%) or extratemporal or multilobar resections (14/28; 50%); or between patients who were (9/16; 56%) or were not (8/19; 42%) studied with subdural electrodes. Results for all analyses were similar when analyzed at latest available follow-up or at 1 year after surgery.
  
  
  CONCLUSIONS
  Surgery can offer seizure-free outcome for approximately one half of carefully selected patients with intractable focal epilepsy due to MCD. Complete resection of the MRI-apparent lesion may improve the likelihood for favorable outcome. MRI evidence of hemimegalencephaly or bilateral MCD suggests a low likelihood for postoperative freedom from seizures.
authors.affiliation: Department of Neurology, Cleveland Clinic Foundation, OH 44195, USA.
authors.forename: J C
authors.initials: JC
authors.lastname: Edwards
authors.forename: E
authors.initials: E
authors.lastname: Wyllie
authors.forename: P M
authors.initials: PM
authors.lastname: Ruggeri
authors.forename: W
authors.initials: W
authors.lastname: Bingaman
authors.forename: H
authors.initials: H
authors.lastname: Lüders
authors.forename: P
authors.initials: P
authors.lastname: Kotagal
authors.forename: D S
authors.initials: DS
authors.lastname: Dinner
authors.forename: H H
authors.initials: HH
authors.lastname: Morris
authors.forename: R A
authors.initials: RA
authors.lastname: Prayson
authors.forename: Y G
authors.initials: YG
authors.lastname: Comair
mesh_terms: D000293:Adolescent; D000328:Adult; D001921:Brain / Q000002:abnormalities* / Q000000981:diagnostic imaging / Q000473:pathology*; D002648:Child; D002675:Child, Preschool; D004827:Epilepsy / Q000209:etiology* / Q000473:pathology* / Q000503:physiopathology / Q000601:surgery; D005260:Female; D006801:Humans; D007223:Infant; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D014055:Tomography, Emission-Computed