title: Pathology-Based Approach to Seizure Outcome After Surgery for Pharmacoresistant Medial Temporal Lobe Epilepsy.
abstract: BACKGROUND
  Hippocampal sclerosis (HS) is the most common cause of drug-resistant medial temporal lobe epilepsy (MTLE). Structural abnormalities such as HS, granule cell pathology (GCP), and focal cortical dysplasia (FCD) have been classified histopathologically, possibly allowing a more accurate assessment of prognostic seizure and neuropsychologic outcomes. We correlated seizure outcome with comprehensive temporal lobe pathologic findings, identified according to the most recent classification systems of HS, GCP, and FCD.
  
  
  METHODS
  All the 83 patients who underwent anterior temporal lobectomy (ATL) for drug-resistant MTLE and with a proven diagnosis of HS between April 2001 and May 2014 were collected. Patients were divided in 2 main groups: 1) isolated HS with/without GCP (HS +/- GCP); and 2) HS associated with FCD with/without GCP (HS+FCD +/- GCP). Patients were followed up at least 1 year, and seizure outcome was reported in accordance with Engel classification.
  
  
  RESULTS
  Group I: HS +/- GCP: Statistical analysis confirmed a better outcome in HS + GCP patients than in HS-no GCP (P < 0.05). Moreover, a better outcome for the patients affected by GCP type I was observed (P < 0.05). Group II: HS+FCD +/- GCP: Patients with HS variant type I presented a better seizure outcome than the patients with HS type II (Engel class IA HS type I vs. type II: 69% vs. 40%).
  
  
  CONCLUSIONS
  A pathology-based approach to epilepsy surgery might improve the interpretation of the results, could predict which cases will enjoy a better seizure outcome, and could help to the comprehension of the causes of failures.
authors.affiliation: IRCCS Institute of Neurological Science of Bologna, Division of Neurosurgery, Bellaria Hospital, Bologna, Italy. Electronic address: matteo.martinoni@gmail.com.
authors.forename: Matteo
authors.initials: M
authors.lastname: Martinoni
authors.affiliation: IRCCS Institute of Neurological Science of Bologna, Division of Neurosurgery, Bellaria Hospital, Bologna, Italy.
authors.forename: Pier Paolo
authors.initials: PP
authors.lastname: Berti
authors.affiliation: Section of Pathology, "M. Malpighi," Bellaria Hospital, Azienda USL-IRCCS Institute of Neurological Sciences, Bologna, Italy.
authors.forename: Gianluca
authors.initials: G
authors.lastname: Marucci
authors.affiliation: IRCCS Institute of Neurological Science of Bologna, Division of Neurology, Bellaria Hospital, Bologna, Italy; Danish Epilepsy Centre, Dianalund, Denmark.
authors.forename: Guido
authors.initials: G
authors.lastname: Rubboli
authors.affiliation: IRCCS Institute of Neurological Science of Bologna, Division of Neurology, Bellaria Hospital, Bologna, Italy.
authors.forename: Lilia
authors.initials: L
authors.lastname: Volpi
authors.affiliation: IRCCS Institute of Neurological Science of Bologna, Division of Neurology, Bellaria Hospital, Bologna, Italy.
authors.forename: Patrizia
authors.initials: P
authors.lastname: Riguzzi
authors.affiliation: IRCCS Institute of Neurological Science of Bologna, Division of Neuroradiology, Bellaria Hospital, Bologna, Italy.
authors.forename: Federica
authors.initials: F
authors.lastname: Marliani
authors.affiliation: IRCCS Institute of Neurological Science of Bologna, Division of Neuroradiology, Bellaria Hospital, Bologna, Italy.
authors.forename: Francesco
authors.initials: F
authors.lastname: Toni
authors.affiliation: IRCCS Institute of Neurological Science of Bologna, Division of Neurology, Bellaria Hospital, Bologna, Italy; Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy.
authors.forename: Francesca
authors.initials: F
authors.lastname: Bisulli
authors.affiliation: IRCCS Institute of Neurological Science of Bologna, Division of Neurology, Bellaria Hospital, Bologna, Italy; Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy.
authors.forename: Paolo
authors.initials: P
authors.lastname: Tinuper
authors.affiliation: IRCCS Institute of Neurological Science of Bologna, Division of Neurology, Bellaria Hospital, Bologna, Italy.
authors.forename: Roberto
authors.initials: R
authors.lastname: Michelucci
authors.affiliation: IRCCS Institute of Neurological Science of Bologna, Division of Neurology, Bellaria Hospital, Bologna, Italy; Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy.
authors.forename: Agostino
authors.initials: A
authors.lastname: Baruzzi
authors.affiliation: IRCCS Institute of Neurological Science of Bologna, Division of Neurosurgery, Bellaria Hospital, Bologna, Italy.
authors.forename: Marco
authors.initials: M
authors.lastname: Giulioni
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D038481:Anterior Temporal Lobectomy; D000069279:Drug Resistant Epilepsy / Q000145:classification / Q000473:pathology* / Q000601:surgery*; D004833:Epilepsy, Temporal Lobe / Q000145:classification / Q000473:pathology* / Q000601:surgery*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D009474:Neurons / Q000473:pathology; D011183:Postoperative Complications; D012189:Retrospective Studies; D012598:Sclerosis / Q000145:classification / Q000473:pathology / Q000601:surgery; D012640:Seizures / Q000145:classification / Q000473:pathology* / Q000601:surgery*; D013702:Temporal Lobe / Q000473:pathology / Q000601:surgery; D016896:Treatment Outcome; D055815:Young Adult
keywords: Epilepsy surgery; Focal cortical dysplasia; Granule cell pathology; Hippocampal sclerosis; Seizure outcome; Temporal lobe epilepsy