title: Prevalence of abnormal pattern reversal visual evoked potentials in craniosynostosis.
abstract: BACKGROUND
  The purpose of this study was to examine the prevalence and type of changes observed in the pattern reversal visual evoked potentials recorded at the first assessment of children with craniosynostosis.
  
  
  METHODS
  Visual evoked potentials were recorded from 114 patients with craniosynostosis. Eighty-one patients were syndromic and 33 were nonsyndromic. No patient had received any craniofacial surgical intervention. At the time of the test, 22 of 40 patients were aged 6 months and younger, and 18 patients were between 6 months and 1 year of age. Pattern reversal visual evoked potentials were recorded from a midoccipital electrode positioned 3 cm above the inion. The pattern reversal visual evoked potentials elicited to 50' checks with three reversals per second viewed with both eyes were analyzed for n80-p100 amplitude, p100 latency, and breadth of waveform.
  
  
  RESULTS
  Sixty percent of patients had abnormal pattern reversal visual evoked potentials to 50' checks. This did not show a significant association with age, or classification of craniosynostosis.
  
  
  CONCLUSIONS
  The high prevalence of abnormal pattern reversal visual evoked potentials to a robust stimulus suggests that visual pathway dysfunction, as measured electrophysiologically, can affect a majority of patients with craniosynostosis. This study indicates that a baseline evaluation of all children with craniosynostosis at their first presentation is essential if subsequent electrophysiologic visual pathway monitoring is to take place.
authors.affiliation: Tony Kriss Visual Electrophysiology Unit and the Department of Ophthalmology, Great Ormond Street Hospital for Children, Great Ormond Street Hospital, London WC1N 3JH, United Kingdom.
authors.forename: Dorothy A
authors.initials: DA
authors.lastname: Thompson
authors.forename: Alki
authors.initials: A
authors.lastname: Liasis
authors.forename: Sharon
authors.initials: S
authors.lastname: Hardy
authors.forename: Richard
authors.initials: R
authors.lastname: Hagan
authors.forename: Richard D
authors.initials: RD
authors.lastname: Hayward
authors.forename: Robert D
authors.initials: RD
authors.lastname: Evans
authors.forename: Kanwal K
authors.initials: KK
authors.lastname: Nischal
mesh_terms: D003398:Craniosynostoses / Q000150:complications / Q000503:physiopathology*; D005074:Evoked Potentials, Visual; D006801:Humans; D007223:Infant; D007427:Intracranial Pressure; D014795:Visual Pathways / Q000503:physiopathology*