title: Extensive maxillary sinus pneumatization.
abstract: OBJECTIVE
  To determine the incidence of variations of maxillary sinus pneumatization especially when it is extensive and the associated anomalies.
  
  
  METHODS
  Two hundred consecutive direct coronal paranasal sinus computed tomography (CT) scans were reviewed retrospectively. Extensive maxillary sinus pneumatization (EMSP) was defined as one in which the largest horizontal and/or vertical dimension of the maxillary sinus equalled or exceeded 90% of the corresponding diameter of the orbit. Further subtype I, II & III were defined depending on whether the pneumatization was extensive in one dimension (horizontal or vertical), two dimensions (horizontal & vertical) and by the presence of sphenomaxillary plate, intermaxillary plate or extension into frontal recess.
  
  
  RESULTS
  EMSP was found in 8%, of these 7% were bilateral and 1% was unilateral. (Subtype I, II and III constituting 1%, 3% & 4% respectively).
  
  
  CONCLUSIONS
  EMSP has been defined as a group and a classification proposed. EMSP will result in an atypical clinical picture, has a role in the pathogenesis of frontal sinusitis in some cases and may predispose injury to the orbit during endoscopic sinus surgery (ESS).
authors.affiliation: Department of Otorhinolaryngology, Warrington General Hospital, Warrington, England, United Kingdom. sudhakiran7@yahoo.com
authors.forename: Sudhakiran
authors.initials: S
authors.lastname: Kalavagunta
authors.forename: K T
authors.initials: KT
authors.lastname: Reddy
mesh_terms: D015522:Frontal Sinusitis / Q000209:etiology; D006801:Humans; D015994:Incidence; D008443:Maxillary Sinus / Q000000981:diagnostic imaging* / Q000473:pathology; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed