title: Seizure characteristics of epilepsy in childhood after acute encephalopathy with biphasic seizures and late reduced diffusion.
abstract: OBJECTIVE
  The aim of this study was to clarify characteristics of post-encephalopathic epilepsy (PEE) in children after acute encephalopathy with biphasic seizures and late reduced diffusion (AESD), paying particular attention to precise diagnosis of seizure types.
  
  
  METHODS
  Among 262 children with acute encephalopathy/encephalitis registered in a database of the Tokai Pediatric Neurology Society between 2005 and 2012, 44 were diagnosed with AESD according to the clinical course and magnetic resonance imaging (MRI) findings and were included in this study. Medical records were reviewed to investigate clinical data, MRI findings, neurologic outcomes, and presence or absence of PEE. Seizure types of PEE were determined by both clinical observation by pediatric neurologists and ictal video-electroencephalography (EEG) recordings.
  
  
  RESULTS
  Of the 44 patients after AESD, 10 (23%) had PEE. The period between the onset of encephalopathy and PEE ranged from 2 to 39 months (median 8.5 months). Cognitive impairment was more severe in patients with PEE than in those without. Biphasic seizures and status epilepticus during the acute phase of encephalopathy did not influence the risk of PEE. The most common seizure type of PEE on clinical observation was focal seizures (n = 5), followed by epileptic spasms (n = 4), myoclonic seizures (n = 3), and tonic seizures (n = 2). In six patients with PEE, seizures were induced by sudden unexpected sounds. Seizure types confirmed by ictal video-EEG recordings were epileptic spasms and focal seizures with frontal onset, and all focal seizures were startle seizures induced by sudden acoustic stimulation. Intractable daily seizures remain in six patients with PEE.
  
  
  CONCLUSIONS
  We demonstrate seizure characteristics of PEE in children after AESD. Epileptic spasms and startle focal seizures are common seizure types. The specific seizure types may be determined by the pattern of diffuse subcortical white matter injury in AESD and age-dependent reorganization of the brain network.
authors.affiliation: Department of Pediatrics, Nagoya University Graduate School of Medicine, Aichi, Japan.|Brain & Mind Research Center, Nagoya University, Aichi, Japan.
authors.forename: Yuji
authors.identifier: http://orcid.org/0000-0003-0460-9588
authors.initials: Y
authors.lastname: Ito
authors.affiliation: Department of Pediatrics, Nagoya University Graduate School of Medicine, Aichi, Japan.|Brain & Mind Research Center, Nagoya University, Aichi, Japan.
authors.forename: Jun
authors.initials: J
authors.lastname: Natsume
authors.affiliation: Department of Pediatrics, Nagoya University Graduate School of Medicine, Aichi, Japan.|Brain & Mind Research Center, Nagoya University, Aichi, Japan.
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Kidokoro
authors.affiliation: Department of Pediatrics, Nagoya University Graduate School of Medicine, Aichi, Japan.|Department of Pediatrics, Fujita Health University School of Medicine, Aichi, Japan.
authors.forename: Naoko
authors.initials: N
authors.lastname: Ishihara
authors.affiliation: Department of Pediatrics, Nagoya University Graduate School of Medicine, Aichi, Japan.
authors.forename: Yoshiteru
authors.initials: Y
authors.lastname: Azuma
authors.affiliation: Department of Pediatrics, Okazaki City Hospital, Aichi, Japan.
authors.forename: Takeshi
authors.initials: T
authors.lastname: Tsuji
authors.affiliation: Department of Pediatrics, Juntendo University Faculty of Medicine, Tokyo, Japan.|Department of Pediatrics, Aichi Medical University, Aichi, Japan.
authors.forename: Akihisa
authors.initials: A
authors.lastname: Okumura
authors.affiliation: Department of Pediatrics, Anjo Kosei Hospital, Aichi, Japan.
authors.forename: Tetsuo
authors.initials: T
authors.lastname: Kubota
authors.affiliation: Department of Pediatrics and Neonatology, Nagoya City University Graduate School of Medical Sciences, Aichi, Japan.
authors.forename: Naoki
authors.initials: N
authors.lastname: Ando
authors.affiliation: Department of Pediatrics and Neonatology, Nagoya City University Graduate School of Medical Sciences, Aichi, Japan.
authors.forename: Shinji
authors.initials: S
authors.lastname: Saitoh
authors.affiliation: Department of Pediatrics, Nagoya University Graduate School of Medicine, Aichi, Japan.
authors.forename: Kiyokuni
authors.initials: K
authors.lastname: Miura
authors.affiliation: Department of Pediatrics, Nagoya University Graduate School of Medicine, Aichi, Japan.
authors.forename: Tamiko
authors.initials: T
authors.lastname: Negoro
authors.affiliation: Department of Pediatrics, Nagoya University Graduate School of Medicine, Aichi, Japan.
authors.forename: Kazuyoshi
authors.initials: K
authors.lastname: Watanabe
authors.affiliation: Department of Pediatrics, Nagoya University Graduate School of Medicine, Aichi, Japan.
authors.forename: Seiji
authors.initials: S
authors.lastname: Kojima
mesh_terms: D002675:Child, Preschool; D003072:Cognition Disorders / Q000209:etiology; D004569:Electroencephalography; D018792:Encephalitis, Viral / Q000150:complications / Q000503:physiopathology* / Q000628:therapy; D004827:Epilepsy / Q000209:etiology / Q000503:physiopathology*; D005260:Female; D005938:Glucocorticoids / Q000627:therapeutic use; D006801:Humans; D016756:Immunoglobulins, Intravenous / Q000627:therapeutic use; D007155:Immunologic Factors / Q000627:therapeutic use; D007223:Infant; D008297:Male; D008775:Methylprednisolone / Q000627:therapeutic use; D019957:Motor Skills Disorders / Q000209:etiology; D013226:Status Epilepticus / Q000209:etiology
chemical_list: D005938:Glucocorticoids; D016756:Immunoglobulins, Intravenous; D007155:Immunologic Factors; D008775:Methylprednisolone
keywords: AESD; Bright tree appearance; Children; Epileptic spasm; Post-encephalopathic epilepsy; Startle seizure