title: Vidian canal: analysis and relationship to the internal carotid artery.
abstract: OBJECTIVE
  The purpose of this study is to describe the anatomy and relationships of the vidian canal to known endonasal and skull base landmarks. This will allow the endoscopic skull base surgeon to safely approach the anterior genu of the petrous carotid artery during expanded endonasal approaches to the skull base.
  
  
  METHODS
  The study is a prospective cohort study.
  
  
  METHODS
  Axial, coronal, and sagittal computed tomography scans of the paranasal sinuses and skull base of 44 patients were examined. Individuals with known skull base pathology were excluded. Measurements included the length of the vidian canal, the relationship of the vidian canal to the anterior genu of the petrous carotid artery, and the type of pneumatization of the sphenoid sinus as it pertains to foramen rotundum and the vidian canal. In addition, we will focus on the relationship of the vidian canal to the sphenopalatine foramen and base of the medial pterygoid plate.
  
  
  RESULTS
  The degree of pneumatization of the sphenoid sinus is highly variable. The mean length of the vidian canal is 18 mm (10-23 mm). The vidian canal is found entirely within bone in 27% to 30% of scans reviewed. The anterior genu of the petrous internal carotid artery is found superior-medial to the vidian canal in 44 of 44 of the CT scans reviewed. The vidian canal runs medial to lateral in 93% to 98% of patients studied.
  
  
  CONCLUSIONS
  As a result of this study the endoscopic skull base surgeon has a number of anatomical landmarks and measurements that may be helpful in safely localizing the anterior genu of the petrous internal carotid artery during expanded endonasal approaches to the skull base.
authors.affiliation: Department of Otolaryngology-Head and Neck Surgery, University of Pittsburgh Medical Center, Pittsburgh, PA 15213, USA.
authors.forename: Allan D
authors.initials: AD
authors.lastname: Vescan
authors.forename: Carl H
authors.initials: CH
authors.lastname: Snyderman
authors.forename: Ricardo L
authors.initials: RL
authors.lastname: Carrau
authors.forename: Arlan
authors.initials: A
authors.lastname: Mintz
authors.forename: Paul
authors.initials: P
authors.lastname: Gardner
authors.forename: Barton
authors.initials: B
authors.lastname: Branstetter
authors.forename: Amin B
authors.initials: AB
authors.lastname: Kassam
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002343:Carotid Artery, Internal / Q000033:anatomy & histology*; D015331:Cohort Studies; D004724:Endoscopy / Q000379:methods; D006801:Humans; D008875:Middle Aged; D011446:Prospective Studies; D019291:Skull Base / Q000033:anatomy & histology* / Q000000981:diagnostic imaging; D013101:Sphenoid Sinus / Q000033:anatomy & histology* / Q000000981:diagnostic imaging; D014057:Tomography, X-Ray Computed