title: How does nose blowing effect the computed tomography of paranasal sinuses in chronic sinusitis?
abstract: OBJECTIVE
  Our aim was to determine whether inward or outward movement of the secretions in the paranasal sinuses due to nose blowing after nasal decongestion has any effect on the paranasal sinus computed tomography (CT) images in patients with sinusitis and to asses whether nose blowing may result in misdiagnosis or overdiagnosis in radiological evaluation of sinusitis.
  
  
  METHODS
  Twenty-four patients with chronic sinusitis were evaluated in an academic tertiary care hospital and data were collected prospectively. After coronal sinus computed tomography scans were performed at 100 mA setting which was half the value of the standard radiation dose suggested by the manufacturer, topical decongestion was applied to each nostril followed by nose blowing 10 min later. Sinus CT scans were then repeated at the same setting. We evaluated the mucosal thickness of medial, lateral, superior and inferior maxillary and frontal sinus walls and the maximal thickness in anterior ethmoidal cells. The measurements prior to and following nose blowing were compared with Wilcoxon signed ranks test. The obtained images were also staged using Lund-McKay staging system separately and the scores were compared with Student's t-test.
  
  
  RESULTS
  We observed a tendency towards reduction in mucosal thickness after nose blowing. There were statistically significant differences between maxillary sinus inferior wall and frontal sinus inferior wall mucosal thickness values prior to and after nose blowing. The difference however was very small, about 0.5 mm in magnitude and Lund-McKay score did not change in any of the patients after nose blowing.
  
  
  CONCLUSIONS
  Nose blowing and topical nasal decongestion does not have any effect on the diagnostic accuracy of sinus CT in chronic sinusitis patients.
authors.affiliation: Department of Radiology, Faculty of Medicine, Zonguldak Karaelmas University, Kozlu, Zonguldak 67600, Turkey. savranlar@yahoo.com
authors.forename: Ahmet
authors.initials: A
authors.lastname: Savranlar
authors.forename: Lokman
authors.initials: L
authors.lastname: Uzun
authors.forename: Mehmet Birol
authors.initials: MB
authors.lastname: Ugur
authors.forename: Kamran
authors.initials: K
authors.lastname: Mahmutyazicioglu
authors.forename: Tulay
authors.initials: T
authors.lastname: Ozer
authors.forename: Sadi
authors.initials: S
authors.lastname: Gundogdu
mesh_terms: D000328:Adult; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009296:Nasal Cavity / Q000502:physiology; D014663:Nasal Decongestants / Q000008:administration & dosage; D010256:Paranasal Sinuses / Q000000981:diagnostic imaging*; D012852:Sinusitis / Q000000981:diagnostic imaging*; D018709:Statistics, Nonparametric; D014057:Tomography, X-Ray Computed
chemical_list: D014663:Nasal Decongestants