title: The nasal airflow in noses with septal perforation: a model study.
abstract: BACKGROUND
  Septal perforation is a common clinical problem in rhinology. Affected patients suffer from a dry nose, crusts as well as recurrent epistaxis and sometimes an inspiratory whistle. The aim of this study was to investigate the underlying flow dynamic mechanisms.
  
  
  METHODS
  The physical flow effects of such pathologies were examined in functional nose models (box models) and anatomically exact models of the nose. Therefore, septal perforations of different sizes and localisations were studied in straight and deviated nasal septa.
  
  
  CONCLUSIONS
  It could be seen that the localisation of the perforation has no impact on the flow pattern. In large septal perforations, the air jet collides with the posterior edge of the perforation and disintegrates turbulently. Since airflow is physiologically turbulent in the posterior part of the nose, posterior perforations do not cause clinical complaints. The inspiratory whistling sound during respiration is based on the principle of a lip whistle. Large perforations do not cause a whistling sound. The necessary high flow velocity needed in large perforations is usually not achievable.
authors.affiliation: Department of Otorhinolaryngology, Head and Neck Surgery, Ernst-Moritz-Arndt University Greifswald, Greifswald, Germany. gruetzen@uni-greifswald.de
authors.forename: S
authors.initials: S
authors.lastname: Grützenmacher
authors.forename: R
authors.initials: R
authors.lastname: Mlynski
authors.forename: C
authors.initials: C
authors.lastname: Lang
authors.forename: S
authors.initials: S
authors.lastname: Scholz
authors.forename: R
authors.initials: R
authors.lastname: Saadi
authors.forename: G
authors.initials: G
authors.lastname: Mlynski
mesh_terms: D006801:Humans; D008953:Models, Anatomic; D015508:Nasal Obstruction / Q000175:diagnosis / Q000209:etiology / Q000503:physiopathology; D009300:Nasal Septum / Q000293:injuries* / Q000503:physiopathology*; D012123:Pulmonary Ventilation / Q000502:physiology*