title: The anatomical variations in the neurovascular relations of the sphenoid sinus: an evaluation by coronal computed tomography.
abstract: OBJECTIVE
  The sphenoid sinus is deeply situated in the skull and is the least accessible paranasal sinus. The sphenoid sinus is surrounded by vital structures such as the optic nerve and internal carotid artery, and therefore additional radiological assessment of the sphenoid sinus and the related neurovascular structures is inevitable before surgery. The aim of this study was to note the anatomic variations in the relationship of these structures with the sphenoid sinus by analyzing the coronal computed tomography (CT) scans.
  
  
  METHODS
  The consecutive coronal CT scans of 100 patients that included 43 males and 57 females were evaluated.
  
  
  RESULTS
  Variations in the neurovascular boundaries of the sphenoid sinus were a common finding in the present study and were seen in as many as 66% of the cases. Variations involving the Vidian canal were the commonest in our study and were seen in around 42%, followed by those involving the bony canal for internal carotid artery, 33%; maxillary nerve, 21 % and optic nerve, 9%.
  
  
  CONCLUSIONS
  These variations do not represent disease as such, but may increase the risk of endoscopic mishaps. CT of the paranasal sinus region is therefore an essential prerequisite prior to sinonasal and trans-sphenoidal surgeries.
authors.affiliation: Kasturba Medical College, Manipal University, Mangalore, Department of Anatomy, Mangalore, India.
authors.forename: Priyadarshini
authors.initials: P
authors.lastname: D
authors.forename: Latha V
authors.initials: LV
authors.lastname: Prabhu
authors.forename: Ashvini
authors.initials: A
authors.lastname: Kumar
authors.forename: Mangala M
authors.initials: MM
authors.lastname: Pai
authors.forename: Dananjay
authors.initials: D
authors.lastname: Kvn
mesh_terms: D000328:Adult; D000368:Aged; D002343:Carotid Artery, Internal / Q000000981:diagnostic imaging*; D003430:Cross-Sectional Studies; D004724:Endoscopy / Q000379:methods; D005260:Female; D006801:Humans; D008297:Male; D008442:Maxillary Nerve / Q000000981:diagnostic imaging*; D008875:Middle Aged; D009900:Optic Nerve / Q000000981:diagnostic imaging*; D012189:Retrospective Studies; D013101:Sphenoid Sinus / Q000033:anatomy & histology* / Q000098:blood supply / Q000000981:diagnostic imaging* / Q000294:innervation; D014057:Tomography, X-Ray Computed / Q000379:methods / Q000592:standards*