title: Drug-resistant focal sleep related epilepsy: results and predictors of surgical outcome.
abstract: In this study we report the results of surgery in a large population of patients affected by drug-resistant focal sleep related epilepsy (SRE) and the identified prognostic factors. We conducted a retrospective analysis of a case series of 955 patients operated on for drug-resistant focal epilepsy from 1997 to 2009. Ninety-five patients with focal SRE and a follow-up of at least 2 years were identified. Presurgical, surgical and histopathological variables were analyzed. Risk of seizures recurrence was assessed by univariate and multivariate analysis. Mean age at epilepsy onset was 5.6 ± 4.9 years. MRI revealed a focal abnormality in 78.9% of cases. Sixty-two percent of patients required a Stereo-EEG investigation. The cortical resection involved the frontal lobe in 61.1% of cases, while in 38.9% an extrafrontal resection was performed. Focal cortical dysplasia (FCD) type II was the most frequent histopathological finding. Mean postoperative follow-up was 82.3 months. Seventy-three patients (76.8%) were in Engel's class I. At univariate analysis, variables associated with a favorable outcome were: absence of Stereo-EEG investigation; positive MRI; complete removal of the epileptogenic zone (EZ); presence of FCD type II and FCD type IIb. A diagnosis of FCD type I was associated with postoperative recurrence of seizures. Multivariate analysis identified the complete removal of the EZ and FCD type I as independent predictors of a favorable and unfavorable outcome respectively. SRE can frequently originate outside the frontal lobe and a favorable surgical outcome is achieved in three-fourths of cases independently from the location of the EZ.
authors.affiliation: Institute of Neurology, Catholic University, Policlinico Universitario A. Gemelli, Rome, Italy.
authors.forename: Anna
authors.initials: A
authors.lastname: Losurdo
authors.affiliation: "C. Munari" Center of Epilepsy Surgery, Niguarda Hospital, Milan, Italy.
authors.forename: Paola
authors.initials: P
authors.lastname: Proserpio
authors.affiliation: "C. Munari" Center of Epilepsy Surgery, Niguarda Hospital, Milan, Italy.
authors.forename: Francesco
authors.initials: F
authors.lastname: Cardinale
authors.affiliation: "C. Munari" Center of Epilepsy Surgery, Niguarda Hospital, Milan, Italy.
authors.forename: Francesca
authors.initials: F
authors.lastname: Gozzo
authors.affiliation: "C. Munari" Center of Epilepsy Surgery, Niguarda Hospital, Milan, Italy.
authors.forename: Laura
authors.initials: L
authors.lastname: Tassi
authors.affiliation: "C. Munari" Center of Epilepsy Surgery, Niguarda Hospital, Milan, Italy.
authors.forename: Roberto
authors.initials: R
authors.lastname: Mai
authors.affiliation: "C. Munari" Center of Epilepsy Surgery, Niguarda Hospital, Milan, Italy.
authors.forename: Stefano
authors.initials: S
authors.lastname: Francione
authors.affiliation: "C. Munari" Center of Epilepsy Surgery, Niguarda Hospital, Milan, Italy.
authors.forename: Laura
authors.initials: L
authors.lastname: Castana
authors.affiliation: "C. Munari" Center of Epilepsy Surgery, Niguarda Hospital, Milan, Italy.
authors.forename: Giorgio
authors.initials: G
authors.lastname: Lo Russo
authors.affiliation: "C. Munari" Center of Epilepsy Surgery, Niguarda Hospital, Milan, Italy.
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Casaceli
authors.affiliation: "C. Munari" Center of Epilepsy Surgery, Niguarda Hospital, Milan, Italy.
authors.forename: Ivana
authors.initials: I
authors.lastname: Sartori
authors.affiliation: Institute of Neurology, Catholic University, Policlinico Universitario A. Gemelli, Rome, Italy.
authors.forename: Giacomo
authors.initials: G
authors.lastname: Della Marca
authors.affiliation: "C. Munari" Center of Epilepsy Surgery, Niguarda Hospital, Milan, Italy.
authors.forename: Massimo
authors.initials: M
authors.lastname: Cossu
authors.affiliation: "C. Munari" Center of Epilepsy Surgery, Niguarda Hospital, Milan, Italy; Institute of Bioimaging and Molecular Physiology, Genoa Unit, National Research Council, Genoa, Italy. Electronic address: Lino.nobili@ospedaleniguarda.it.
authors.forename: Lino
authors.initials: L
authors.lastname: Nobili
mesh_terms: D000927:Anticonvulsants / Q000627:therapeutic use; D001921:Brain / Q000473:pathology / Q000503:physiopathology / Q000601:surgery; D004569:Electroencephalography; D004827:Epilepsy / Q000175:diagnosis* / Q000473:pathology / Q000503:physiopathology / Q000601:surgery*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D011379:Prognosis; D012008:Recurrence; D012189:Retrospective Studies; D012640:Seizures / Q000175:diagnosis / Q000473:pathology / Q000503:physiopathology / Q000601:surgery; D012893:Sleep Wake Disorders / Q000175:diagnosis / Q000473:pathology / Q000503:physiopathology / Q000601:surgery; D016896:Treatment Outcome; D055815:Young Adult
chemical_list: D000927:Anticonvulsants
keywords: Epilepsy; Epilepsy surgery; Sleep; Sleep related epilepsy