title: Severe posterior epistaxis-endoscopic surgical anatomy.
abstract: OBJECTIVE
  To describe the anatomy of the sphenopalatine foramen (SPF) region and possible anatomical variations.
  
  
  METHODS
  Prospective study accomplished from September, 2006, to January, 2007.
  
  
  METHODS
  The sphenopalatine foramen (SPF) of 61 cadavers were carefully dissected. Presence of the ethmoidal crest, location of sphenopalatine and accessory foramens, and the number of arterial branches emerging through foramens were observed. Data were analyzed in relation to gender, racial group, and symmetry of the cadaver. Prediction of the presence of accessory foramen was evaluated.
  
  
  RESULTS
  Mixed race cadavers prevailed in 122 nasal fossae dissected (75% males). Ethmoidal crest was present in 100% of the cadavers, being anterior to the SPF in 98.4% of the cases. The most frequent SPF location was the transition of the middle and superior meatus (86.9%). Mean distance from the SPF and accessory foramen to anterior nasal spine was 6.6 cm and 6.7 cm, respectively. Accessory foramen was present in 9.83% of the cases. A single arterial stem emerged through the SPF in 67.2% of the cases, and 100% through accessory foramens. The prevalence analyses showed no differences that were statistically significant (P > 0.05) between gender and racial group. The symmetry analyses showed a strong conformity (P < 0.01) between nasal fossae in relation to the SPF location. There was no statistically significant conformity between nasal fossae and accessory foramen (P = 0.53). None of the variables of interest presents any statistically significant (P > 0.05) association with the presence of the accessory foramen.
  
  
  CONCLUSIONS
  There are anatomical variations in the lateral nose wall that should be considered for successful endoscopic surgical treatment of severe epistaxis.
authors.affiliation: Clinical Hospital of the Medical University of São Paulo, São Paulo-SP, Brazil. franciniotorrino@gmail.com
authors.forename: Francini G M
authors.initials: FG
authors.lastname: Pádua
authors.forename: Richard L
authors.initials: RL
authors.lastname: Voegels
mesh_terms: D001158:Arteries / Q000473:pathology; D002102:Cadaver; D004210:Dissection; D004724:Endoscopy / Q000379:methods*; D004844:Epistaxis / Q000601:surgery*; D005004:Ethmoid Bone / Q000473:pathology; D005260:Female; D006801:Humans; D008297:Male; D009295:Nasal Bone / Q000473:pathology; D010159:Palate / Q000098:blood supply / Q000473:pathology* / Q000601:surgery; D011446:Prospective Studies; D044469:Racial Groups; D012737:Sex Factors; D013100:Sphenoid Bone / Q000098:blood supply / Q000473:pathology* / Q000601:surgery