title: Sleep apnoea in syndromic craniosynostosis occurs independent of hindbrain herniation.
abstract: OBJECTIVE
  Hindbrain herniation (HH) is frequently found in syndromic craniosynostosis. It may cause impairment of the respiratory centres and manifest as sleep-disordered breathing. Our aim was to quantify sleep apnoea caused by HH in children with syndromic craniosynostosis.
  
  
  METHODS
  Seventy-one children with syndromic and complex craniosynostosis (aged 0-18 years) underwent prospective magnetic resonance imaging and a sleep study. The position of the cerebellar tonsils and respiratory parameters were evaluated and analysed. None of the included patients had undergone previous foramen magnum decompression.
  
  
  RESULTS
  HH was present in 35% of the patients and was more frequent in children with Crouzon syndrome (63%) than in other types of craniosynostosis (p = .018). There was a positive association between the position of the cerebellar tonsils and papilledema (p = .002). Sleep studies of children with craniosynostosis and HH were not different from those without HH. Obstructive sleep apnoea syndrome was not more prevalent in children with HH compared to those without HH (p = .12). A cluster analysis using indices of apnoea revealed that three new clusters between which age was significantly different (p = .025).
  
  
  CONCLUSIONS
  Sleep apnoea in syndromic craniosynostosis is not caused by HH. Rather, our evidence suggests that sleep-disordered breathing in craniosynostosis may be caused by brain stem immaturity in young children or upper airway obstruction. Therefore, as long as the child remains asymptomatic, our preferred management of HH is to be conservative and provide regular neurosurgical follow-up.
authors.affiliation: Department of Plastic, Reconstructive and Hand Surgery, Dutch Craniofacial Centre, Sophia Children's Hospital, Erasmus MC, Rotterdam, The Netherlands. c.driessen@erasmusmc.nl
authors.forename: Caroline
authors.initials: C
authors.lastname: Driessen
authors.forename: Koen F M
authors.initials: KF
authors.lastname: Joosten
authors.forename: Joyce M G
authors.initials: JM
authors.lastname: Florisson
authors.forename: Maarten
authors.initials: M
authors.lastname: Lequin
authors.forename: Marie-Lise C
authors.initials: ML
authors.lastname: van Veelen
authors.forename: Rúben
authors.initials: R
authors.lastname: Dammers
authors.forename: Hansje
authors.initials: H
authors.lastname: Bredero-Boelhouwer
authors.forename: Robert C
authors.initials: RC
authors.lastname: Tasker
authors.forename: Irene M J
authors.initials: IM
authors.lastname: Mathijssen
mesh_terms: D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D003398:Craniosynostoses / Q000175:diagnosis* / Q000453:epidemiology*; D004677:Encephalocele / Q000175:diagnosis* / Q000453:epidemiology*; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D011446:Prospective Studies; D012249:Rhombencephalon / Q000473:pathology; D012891:Sleep Apnea Syndromes / Q000175:diagnosis* / Q000453:epidemiology*; D013577:Syndrome; D055815:Young Adult