title: Analysis of the influence of head rotation during drug-induced sleep endoscopy in obstructive sleep apnea.
abstract: OBJECTIVE
  Currently, drug-induced sleep endoscopy (DISE) in obstructive sleep apnea (OSA) is predominantly performed in supine position. When positional therapy (avoidance of supine sleeping position in positional OSA (POSA) is implemented as (part of the) treatment, one should assess levels of obstruction in the other sleeping positions. Therefore, the current study examined the influence of difference head positions during DISE in patients with OSA and POSA.
  
  
  METHODS
  Consecutive prospective study.
  
  
  METHODS
  DISE was performed in patients with an apnea hypopnea index at baseline polysomnography greater than 5 events/h. The upper airway was assessed at velum, oropharynx, tongue base, and epiglottis level in supine position. The patients head were then tilted to the left and the right side and the DISE findings were recorded.
  
  
  RESULTS
  One hundred consecutive patients were included. In positional apneics (n = 67), lateral position was associated with decreased frequency of complete anteroposterior collapse at velum (P < 0.01), tongue base (P < 0.01), and epiglottis (P < 0.01) level-and increased frequency of partial anteroposterior collapse at velum (P < 0.01), tongue base (P < 0.01), and epiglottis (P <0.05) level in comparison with supine position. DISE findings showed no difference between the right and left position, whereas findings after head rotation were significantly different in comparison with the supine position.
  
  
  CONCLUSIONS
  Head rotation improves upper airway collapse during DISE in supine position. This improvement of upper airway patency is more predominant in POSA patients.
authors.affiliation: Department of Otolaryngology/Head Neck Surgery, Sint Lucas Andreas Hospital, Amsterdam, The Netherlands.
authors.forename: Faiza
authors.initials: F
authors.lastname: Safiruddin
authors.forename: Ioannis
authors.initials: I
authors.lastname: Koutsourelakis
authors.forename: Nico
authors.initials: N
authors.lastname: de Vries
mesh_terms: D004724:Endoscopy; D005260:Female; D006257:Head; D006801:Humans; D008297:Male; D008875:Middle Aged; D056888:Patient Positioning; D011446:Prospective Studies; D012399:Rotation; D012890:Sleep / Q000187:drug effects; D020181:Sleep Apnea, Obstructive / Q000175:diagnosis*
keywords: Obstructive sleep apnea; drug-induced sleep endoscopy; position dependant sleep apnea