title: Evaluation of acoustic characteristics of snoring sounds obtained during drug-induced sleep endoscopy.
abstract: BACKGROUND
  Snoring sounds are discussed to contain acoustic information about their geneses. Nocturnal snoring can easily be recorded acoustically but it is difficult to visually verify its genesis. Contrary, snoring patterns induced by drug-induced sleep endoscopy (DISE) can be visually differentiated. The aim of the study was to classify patterns of obstructions and vibration during DISE and to evaluate acoustic characteristics between these different patterns of snoring.
  
  
  METHODS
  DISE was performed in 41 male patients with sleep-disordered breathing. The recorded video sequences (n = 108) were classified visually at a mute mode in different patterns of snoring (velar, velar obstructive, tonsillar, post-apnoeic). The sound tracks of these subgroups were analysed and compared with regard to the parameters sound pressure level, loudness, sharpness, roughness, fluctuations strength and centre frequency.
  
  
  RESULTS
  Obstructive snoring patterns revealed a higher loudness than non-obstructive patterns (>25 sone). Velar snoring showed more roughness (>150 cAsper) than tonsillar and post-apnoeic snoring and revealed the lowest centre frequency (<3000 Hz) of all patterns. Tonsillar snoring presented the highest sharpness (>1.6 acum) whereas post-apnoeic snoring revealed the largest fluctuation strength (>50 cVacil).
  
  
  CONCLUSIONS
  Different snoring patterns induced by DISE can be classified visually, and an approach to differentiate them acoustically by means of psychoacoustic analyses is demonstrated. On the basis of these results, nocturnal snoring might also be differentiated by psychoacoustic algorithms which could be implemented in acoustic polygraphic screening devices in the future.
authors.affiliation: Department of Otorhinolaryngology, Head and Neck Surgery, Martin-Luther-University Halle-Wittenberg, Ernst-Grube-Straße 40, 01620, Halle (Saale), Germany, michael.herzog@uk-halle.de.
authors.forename: Michael
authors.initials: M
authors.lastname: Herzog
authors.forename: Sebastian
authors.initials: S
authors.lastname: Plößl
authors.forename: Alexander
authors.initials: A
authors.lastname: Glien
authors.forename: Beatrice
authors.initials: B
authors.lastname: Herzog
authors.forename: Christian
authors.initials: C
authors.lastname: Rohrmeier
authors.forename: Thomas
authors.initials: T
authors.lastname: Kühnel
authors.forename: Stefan
authors.initials: S
authors.lastname: Plontke
authors.forename: Patrick
authors.initials: P
authors.lastname: Kellner
mesh_terms: D000402:Airway Obstruction / Q000175:diagnosis / Q000503:physiopathology; D000771:Anesthesia, Intravenous; D003937:Diagnosis, Differential; D004724:Endoscopy; D006801:Humans; D008297:Male; D008875:Middle Aged; D010160:Palate, Soft / Q000503:physiopathology; D014066:Palatine Tonsil / Q000503:physiopathology; D017286:Polysomnography; D015742:Propofol; D020181:Sleep Apnea, Obstructive / Q000175:diagnosis* / Q000503:physiopathology*; D012913:Snoring / Q000175:diagnosis* / Q000503:physiopathology*; D013018:Sound Spectrography; D014732:Vibration; D014741:Video Recording
chemical_list: D015742:Propofol