title: The effects of posterior fossa decompressive surgery in adult patients with Chiari malformation and sleep apnea.
abstract: OBJECTIVE
  One of the feared consequences of craniovertebral junction diseases is apnea. Although several cases of patients with central apnea have been described, obstructive sleep apnea has been identified as the most frequent manifestation of sleep respiratory disorder. Neuronal involvement may be responsible for both central and obstructive apneas. The objective of this work was to study the effect of posterior fossa decompressive surgery on respiratory parameters during sleep in patients with craniovertebral junction malformations and breathing-related sleep disorders.
  
  
  METHODS
  In this study, prospectively enrolled consecutive symptomatic adult patients were monitored with full-night polysomnography before and after surgical decompression of the cranial posterior fossa.
  
  
  RESULTS
  Of the 25 patients who were evaluated, 68% received a diagnosis of sleep apnea. After surgery, the mean number of respiratory events decreased from 180.70 to 69.29 (p = 0.005); the mean number of obstructive events decreased from 107.37 to 60.58 (p = 0.01); and the mean number of central events decreased from 38.45 to 8.05 (p = 0.01). The mean preoperative apnea/hypopnea index decreased from 26.68 to 12.98 (p = 0.06), and the mean central apnea index decreased from 13.81 to 1.68 (p = 0.01).
  
  
  CONCLUSIONS
  Decompressive surgery in patients with craniovertebral junction malformations resulted in decreased respiratory events during sleep, lowered sleep fragmentation, and enhanced the sleep apnea index in a significant number of patients. The effect was more pronounced in patients with central apnea.
authors: Neurosurgical Service, Hospital do Servidor publico do Estado de São Paulo, São Paulo, Brazil. bitbot@uol.com.br
authors: Ricardo Vieira
authors: RV
authors: Botelho
authors: Lia Rita Azeredo
authors: LR
authors: Bittencourt
authors: José Marcus
authors: JM
authors: Rotta
authors: Sérgio
authors: S
authors: Tufik
mesh_terms: D000328:Adult; D001139:Arnold-Chiari Malformation / Q000150:complications / Q000473:pathology / Q000601:surgery*; D003388:Cranial Fossa, Posterior / Q000601:surgery*; D019299:Decompression, Surgical; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D019635:Neurosurgical Procedures; D017286:Polysomnography; D011446:Prospective Studies; D012890:Sleep; D012891:Sleep Apnea Syndromes / Q000209:etiology / Q000473:pathology / Q000601:surgery*; D016896:Treatment Outcome