title: Comparison of anatomical abnormalities in patients with limited and diffuse chronic rhinosinusitis.
abstract: BACKGROUND
  The role of anatomical abnormalities in the pathogenesis of chronic rhinosinusitis (CRS) remains unclear. We hypothesized that anatomical abnormalities causing obstruction of mucus drainage would be more prevalent in patients with limited CRS than in patients with pansinusitis, who are more likely to have a generalized mucosal abnormality.
  
  
  METHODS
  The computed tomography (CT) scans of patients with limited sinusitis (maxillary sinus and/or the ostiomeatal unit), patients with diffuse bilateral disease, and asymptomatic controls were studied. Lund-Mackay scores were calculated and the frequency of anatomical abnormalities that could affect mucus drainage of the ostiomeatal region was determined.
  
  
  RESULTS
  The limited disease group comprised 22 patients with 96 total anatomical variants (4.4 ± 2.0; mean number of variants per patient ± standard deviation [SD]). The diffuse disease group comprised 28 patients with 70 anatomical variants (2.6 ± 2.0). The control group had 27 patients with 68 variants (2.5 ± 1.4). The frequency of total anatomical variants in the limited group was significantly higher than in the pansinusitis and control groups (p < 0.003). There was no significant difference in the total number of anatomical variations between the diffuse disease and control groups. Concha bullosae and accessory ostia were more prevalent in the local disease group than the diffuse disease group. (p < 0.01).
  
  
  CONCLUSIONS
  These results suggest that patients with limited CRS may be predisposed by anatomical variants impairing drainage of the ostiomeatal region, and pansinusitis (likely resulting from generalized mucosal abnormality) is associated with a lower frequency of anatomical variants similar to the general population.
authors.affiliation: Department of Surgery, The University of Auckland, Grafton, Auckland, New Zealand.
authors.forename: Ravi
authors.initials: R
authors.lastname: Jain
authors.forename: Nick
authors.initials: N
authors.lastname: Stow
authors.forename: Richard
authors.initials: R
authors.lastname: Douglas
mesh_terms: D000328:Adult; D016022:Case-Control Studies; D002908:Chronic Disease; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009093:Mucus / Q000378:metabolism; D009296:Nasal Cavity / Q000002:abnormalities* / Q000000981:diagnostic imaging; D009298:Nasal Polyps / Q000000981:diagnostic imaging; D010256:Paranasal Sinuses / Q000002:abnormalities* / Q000000981:diagnostic imaging; D012220:Rhinitis / Q000000981:diagnostic imaging*; D012852:Sinusitis / Q000000981:diagnostic imaging*; D014057:Tomography, X-Ray Computed / Q000379:methods; D014420:Turbinates / Q000002:abnormalities / Q000000981:diagnostic imaging