title: Relationship between initial electroencephalographic characteristics and seizure outcomes in children with non-lesional West syndrome.
abstract: BACKGROUND
  To characterize the initial interictal electroencephalography (EEG) activities associated with seizure outcomes in children with non-lesional West syndrome (WS), and their worth in the prediction of seizure-free (SF) vs no seizure-free (No-SF) outcomes.
  
  
  METHODS
  We retrospectively reviewed the initial scalp EEGs for at least a 40-min duration, and the medical records of 66 children who were diagnosed as WS with normal MRI, and who were followed-up with for 4.5 ± 2.1 years. We assessed the following clinical and EEG findings: onset of seizures, development, underlying etiologies, initial interictal EEGs, and seizure evolution. These variables were compared between two groups: SF vs No-SF groups.
  
  
  RESULTS
  In total, 36 (54.5%) children had SF outcomes and 30 (45.5%) had No-SF outcomes during long-term follow-up (4.4 ± 2.3 vs 4.6 ± 2.0 years, p = 0.7644). The mean age at seizure onset was similar in the SF and No-SF groups (6.0 ± 3.0 vs 6.9 ± 3.2 months, p = 0.2443). Delayed development before the onset of spasms was similarly observed in both groups (13.9% vs 13.3%). Initial EEG findings significantly differed with typical hypsarrhythmia (41.7% vs 73.3%, p = 0.0098), multiple independent spike foci (MISF) (55.6% vs 83.3%, p = 0.0158), frontal-dominant MISF (0.0% vs 40.0%, p < 0.0001), and frontal-dominant generalized epileptiform discharges (EDs) (0.0% vs 16.7%, p=0.0108) being involved more infrequently in the SF group than in the No-SF group, respectively. Patients in the SF group showed no frontal-dominant MISF or frontal-dominant generalized EDs, and a more often normal to borderline sleep-spindle (83.3% vs 40.0%, p = 0.0002) than the No-SF group.
  
  
  CONCLUSIONS
  Patients with SF outcomes more frequently showed the posterior-dominant generalized EDs and normal to borderline sleep-spindle, and the No-SF group more often had typical hypsarrhythmia, frontal-dominant MISF, frontal-dominant generalized EDs, and no normal sleep-spindle. Initial interictal EEG findings may predict seizure outcomes in patients with non-lesional WS.
authors.affiliation: Department of Pediatrics, Pusan National University Children's Hospital, Pusan National University School of Medicine, Yangsan, Republic of Korea; Research Institute for Convergence of Biomedical Science and Technology, Pusan National University Yangsan Hospital, Yangsan, Republic of Korea. Electronic address: jinnyeye@hanmail.net.
authors.forename: Yun-Jin
authors.initials: YJ
authors.lastname: Lee
authors.affiliation: Department of Pediatrics, Kosin University Gospel Hospital, Kosin University, Busan, Republic of Korea. Electronic address: ygmcu@hanmail.net.
authors.forename: Gyu Min
authors.initials: GM
authors.lastname: Yeon
authors.affiliation: Department of Pediatrics, Pusan National University Hospital, Busan, Republic of Korea. Electronic address: pink2129@naver.com.
authors.forename: Young Mi
authors.initials: YM
authors.lastname: Kim
authors.affiliation: Department of Pediatrics, Pusan National University Children's Hospital, Pusan National University School of Medicine, Yangsan, Republic of Korea; Research Institute for Convergence of Biomedical Science and Technology, Pusan National University Yangsan Hospital, Yangsan, Republic of Korea. Electronic address: neuroped@naver.com.
authors.forename: Sang Ook
authors.initials: SO
authors.lastname: Nam
mesh_terms: D017668:Age of Onset; D000927:Anticonvulsants / Q000627:therapeutic use; D001921:Brain / Q000473:pathology / Q000503:physiopathology*; D003936:Diagnosis, Computer-Assisted; D055423:Diet, Ketogenic; D018572:Disease-Free Survival; D004569:Electroencephalography; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007223:Infant; D008279:Magnetic Resonance Imaging; D008297:Male; D011379:Prognosis; D012189:Retrospective Studies; D012640:Seizures / Q000175:diagnosis* / Q000473:pathology / Q000503:physiopathology* / Q000628:therapy; D012890:Sleep / Q000502:physiology; D013036:Spasms, Infantile / Q000175:diagnosis* / Q000473:pathology / Q000503:physiopathology* / Q000628:therapy; D016896:Treatment Outcome
chemical_list: D000927:Anticonvulsants
keywords: EEG; Prognosis; Seizures; West syndrome