title: Comparison of the area of the pharynx during wakefulness and induced sleep in patients with obstructive sleep apnea (OSA).
abstract: The study of obstructive sleep apnea (OSA) has received growing attention over the past years since various aspects have not been sufficiently established.
  
  
  OBJECTIVE
  To evaluate, with the use of magnetic resonance imaging (MRI), changes in the area of the pharynx during wakefulness and induced sleep in patients with OSA.
  
  
  METHODS
  A prospective study of thirty-two patients with a polysomnographic diagnosis of OSA. All patients were submitted to MR imaging in order to obtain high-definition anatomical sagittal sequences during wakefulness and during sleep induced with Propofol. An area was defined on the sagittal plane in the midline of the pharynx. This region was called pharyngeal midplane (PMP) area.
  
  
  RESULTS
  A significant difference in PMP area (mm²) was observed between wakefulness and induced sleep in each patient (p < 0.000001).
  
  
  CONCLUSIONS
  The patients with OSA suffer a significant reduction of 75.5 % in the area of the pharynx during induced sleep compared to wakefulness.
authors.affiliation: Integrated Center for the Study of Facial Deformities-Centro Integrado de Estudo das Deformidades da Face-CIEDEF, Clinic Hospital, Ribeirão Preto Medical School, São Paulo University-USP.
authors.forename: Ana Célia
authors.initials: AC
authors.lastname: Faria
authors.forename: Luis Vicente
authors.initials: LV
authors.lastname: Garcia
authors.forename: Antonio Carlos Dos
authors.initials: AC
authors.lastname: Santos
authors.forename: Paula Rejane Beserra
authors.initials: PR
authors.lastname: Diniz
authors.forename: Helcio Tadeu
authors.initials: HT
authors.lastname: Ribeiro
authors.forename: Francisco Veríssimo de
authors.initials: FV
authors.lastname: Mello-Filho
mesh_terms: D000293:Adolescent; D000328:Adult; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009929:Organ Size; D010614:Pharynx / Q000473:pathology*; D017286:Polysomnography; D011446:Prospective Studies; D012890:Sleep; D020181:Sleep Apnea, Obstructive / Q000473:pathology*; D014851:Wakefulness; D055815:Young Adult