title: [Documentation of endonasal changes in blood volume using optical rhinometry].
abstract: BACKGROUND
  In optical rhinometry, the nose is transilluminated with light and the light absorption by the nasal tissue is measured continuously. Using this method, a real time documentation of changes in nasal blood volume is possible. The method has been evaluated using the nasal allergen provocation test. In this study, the ability of optical rhinometry to detect changes in the nasal blood volume due to various posture changes is examined.
  
  
  METHODS
  Optical rhinometry was tested on ten healthy probands, with several examinations being performed on each.
  
  
  RESULTS
  By bending the neck, lying down or stopping breathing, stronger light extinction was found. Standing up quickly caused a sudden but short decrease in light extinction. A small amount of exercise, such as making a fist several times, decreased light extinction. Harder exercise on an ergometer led to a stronger decrease in light extinction. In the Valsalva maneuver, an increase in light extinction for the duration of the maneuver was observed. Changes in breathing through the nose or mouth or counting from 1 to 100 had no influence.
  
  
  CONCLUSIONS
  Using the new method of optical rhinometry, it is possible to detect changes in endonasal blood volume caused by changes of intrathoracic pressure, changes in posture or physical exercise, non-invasively and in real time. This technique can therefore be used for further research on the regulation of the nasal blood flow.
authors.affiliation: Universitäts-HNO-Klinik, Dresden. eike.wuestenberg@uniklinikum-dresden.de
authors.forename: E G
authors.initials: EG
authors.lastname: Wüstenberg
authors.forename: T
authors.initials: T
authors.lastname: Zahnert
mesh_terms: D000328:Adult; D001810:Blood Volume / Q000502:physiology*; D003936:Diagnosis, Computer-Assisted / Q000379:methods*; D003948:Diagnostic Techniques, Respiratory System; D004282:Documentation / Q000379:methods; D005260:Female; D006801:Humans; D008297:Male; D009666:Nose / Q000098:blood supply* / Q000502:physiology*; D055095:Optics and Photonics; D005082:Physical Exertion / Q000502:physiology*; D012031:Refractometry / Q000379:methods*; D012212:Rheology / Q000379:methods; D023842:Rhinometry, Acoustic / Q000379:methods