title: Atonic elements combined or uncombined with epileptic spasms in infantile spasms.
abstract: OBJECTIVE
  To study the atonic elements combined or uncombined with epileptic spasms in infantile spasms.
  
  
  METHODS
  The demographic data, clinical characteristics, electroencephalogram (EEG), and polyelectromyography (PEMG) features were analyzed in 12 infantile spasm patients with atonic elements.
  
  
  RESULTS
  A total of 29 EEGs were recorded. Hypsarrhythmia or hypsarrhythmia variants were identified during interictal EEG. Insular or clustered epileptic spasms occurred in all. Three subtypes of atonic elements combined or uncombined with epileptic spasms (spasm-atonic, pure atonic, and atonic-spasm seizures) were observed electroclinically, which could present insularly or in cluster or altered with epileptic spasms in the same cluster. The ictal EEG showed generalized high-amplitude slow waves presenting alone or combined with other patterns. The corresponding PEMG showed an obvious electrical silence alone or preceding or following a crescendo-decrescendo pattern generated from myoelectric burst.
  
  
  CONCLUSIONS
  Atonic elements combined or uncombined with epileptic spasms was a newly noticed phenomenon in infantile spasms, which was artificially divided into three subtypes here. It might be a variant of epileptic spasms or a unique seizure type.
  
  
  CONCLUSIONS
  Atonic elements combined or uncombined with epileptic spasms was a previously ignored phenomenon in infantile spasms, which should be seriously considered in clinical practice.
authors.affiliation: Department of Pediatrics, Peking University First Hospital, Beijing, China.
authors.forename: Jiao
authors.initials: J
authors.lastname: Xue
authors.affiliation: Department of Pediatrics, Peking University First Hospital, Beijing, China.
authors.forename: Ping
authors.initials: P
authors.lastname: Qian
authors.affiliation: Department of Pediatrics, Peking University First Hospital, Beijing, China.
authors.forename: Hui
authors.initials: H
authors.lastname: Li
authors.affiliation: Department of Pediatrics, Peking University First Hospital, Beijing, China.
authors.forename: Haipo
authors.initials: H
authors.lastname: Yang
authors.affiliation: Department of Pediatrics, Peking University First Hospital, Beijing, China.
authors.forename: Xiaoyan
authors.initials: X
authors.lastname: Liu
authors.affiliation: Department of Pediatrics, Peking University First Hospital, Beijing, China.
authors.forename: Yuehua
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Department of Pediatrics, Peking University First Hospital, Beijing, China. Electronic address: zhixian.yang@163.com.
authors.forename: Zhixian
authors.initials: Z
authors.lastname: Yang
mesh_terms: D004569:Electroencephalography / Q000379:methods*; D004576:Electromyography / Q000379:methods*; D004832:Epilepsy, Absence / Q000175:diagnosis* / Q000453:epidemiology / Q000503:physiopathology*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D012189:Retrospective Studies; D013036:Spasms, Infantile / Q000175:diagnosis* / Q000453:epidemiology / Q000503:physiopathology*
keywords: Atonic seizures; Epileptic spasms; Infantile spasms