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Epileptogenesis After Ischemic-Hypoxic Encephalopathy

  • Russell M. Sanchez
Reference work entry

Introduction and Definitions

Hypoxic-ischemic encephalopathy (HIE) most commonly refers to neonatal brain injury that results from insufficient brain oxygenation. HIE can occur due to systemic hypoxemia, decreased cerebral blood flow, or both, and acute symptomatic seizures frequently comprise part of the encephalopathy. Hypoxia is a major cause of neonatal seizures, accounting for as much as 60% of all neonatal seizures. Approximately 25–30% of term infants who experienced neonatal seizures will develop epilepsy, and thus, the occurrence of neonatal seizures associated with a hypoxic/ischemic event significantly increases the risk to develop epilepsy. Additional neurological sequelae can include cognitive delay and motor deficits. Currently, the pathophysiological mechanisms that trigger acute seizures and those that mediate epileptogenesis consequent to HIE are poorly understood.

Etiology or Methods

Although the underlying cause may not be identified in all individuals, perinatal HIE...

Keywords

Mossy Fiber White Matter Injury Neonatal Seizure Excitatory Synaptic Transmission Spontaneous Seizure 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer-Verlag London Limited 2010

Authors and Affiliations

  • Russell M. Sanchez
    • 1
  1. 1.College of Medicine, Texas A&M Health Science CenterScott & White Hospital, Central Texas Veterans Health Care SystemTempleUSA

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