title: Microscopic mild focal cortical dysplasia in temporal lobe dual pathology: an electrocorticography study.
abstract: BACKGROUND
  Associations between electrophysiological and histological findings might provide an insight into the epileptogenicity of mild focal cortical dysplasia (FCD) in patients with temporal lobe epilepsy (TLE) and a dual pathology.
  
  
  METHODS
  A total of 22 patients with pharmacoresistant TLE were included in the study, 16 of them with histologically confirmed hippocampal sclerosis (HS) associated with neocortical temporal mild Palmini Type-I FCD subtypes and 6 with HS. Intraoperative electrocorticography (ECoG) recordings were analysed for epileptiform discharge frequency and morphology. Associations between histological, and electrocorticography pattern findings in these patients were analysed. Electroclinical outcomes in these patients were also evaluated.
  
  
  RESULTS
  Neocortical areas with mild Palmini Type-I FCD showed a significantly higher spike frequency (SF) recorded in the inferior temporal gyrus than those neocortical areas in patients with HS. There was a tendency to higher spike frequency and lower amplitude in neocortical areas with histopathologic subtype IB FCD in relation with IA during intraoperative ECoG. Post-SF excision and amplitude were significantly lower during neocortical post-excision intraoperative ECoG than during neocortical pre-excision recording. There was no difference found in the clinical outcome between patients with and without FCD.
  
  
  CONCLUSIONS
  Intraoperative electrocorticographic interictal spike frequency recorded in the neocortical inferior temporal gyrus may help to characterize the histopathologic subtypes of mild Palmini Type-I FCD in patients with temporal lobe epilepsy (TLE) and a dual pathology. Our data support the epileptogenicity of neocortical mild FCD in TLE and assessments of ECoG patterns are relevant to determine the extent of the resection in these patients which can influence the electroclinical outcome.
authors.affiliation: Surgery Epilepsy Program, International Center for Neurological Restoration, Ave 25 No 15 805, Playa, C, Havana CP 11 300, Cuba. lilia.morales@infomed.sld.cu
authors.forename: L
authors.initials: L
authors.lastname: Morales Chacón
authors.forename: B
authors.initials: B
authors.lastname: Estupiñán
authors.forename: L
authors.initials: L
authors.lastname: Lorigados Pedre
authors.forename: O
authors.initials: O
authors.lastname: Trápaga Quincoses
authors.forename: I
authors.initials: I
authors.lastname: García Maeso
authors.forename: A
authors.initials: A
authors.lastname: Sanchez
authors.forename: J
authors.initials: J
authors.lastname: Bender del Busto
authors.forename: M E
authors.initials: ME
authors.lastname: Garcia
authors.forename: M
authors.initials: M
authors.lastname: Baez Martin
authors.forename: M
authors.initials: M
authors.lastname: Zaldivar
authors.forename: A
authors.initials: A
authors.lastname: Gómez
authors.forename: S
authors.initials: S
authors.lastname: Orozco
authors.forename: L
authors.initials: L
authors.lastname: Rocha Arrieta
mesh_terms: D000293:Adolescent; D000328:Adult; D038481:Anterior Temporal Lobectomy / Q000379:methods; D004569:Electroencephalography / Q000379:methods*; D004833:Epilepsy, Temporal Lobe / Q000473:pathology* / Q000503:physiopathology* / Q000601:surgery; D005260:Female; D005500:Follow-Up Studies; D006624:Hippocampus / Q000473:pathology; D006801:Humans; D008297:Male; D054220:Malformations of Cortical Development / Q000473:pathology* / Q000503:physiopathology / Q000601:surgery; D008875:Middle Aged; D019579:Neocortex / Q000473:pathology* / Q000503:physiopathology; D012189:Retrospective Studies; D016896:Treatment Outcome; D055815:Young Adult