title: Endonasal endoscopic exposure of the internal carotid artery: an anatomical study.
abstract: OBJECTIVE
  The aim of this work was to define the anatomical landmarks, limitations, and difficulties of obtaining internal carotid artery (ICA) exposure via endonasal endoscopic approaches (EEA).
  
  
  METHODS
  Cadaveric descriptive study.
  
  
  METHODS
  The ICA was dissected via EEA in 10 cadaveric specimens (20 sides) prepared with intravascular injections of colored silicone. We carried the ICA dissection from the cavernous to the distal parapharyngeal segments through a transpterygoid corridor.
  
  
  RESULTS
  The transpterygoid approach provided adequate exposure of the lacerum and horizontal petrous ICA. Additional exposure of the ICA and the infrapetrous area required resection of the eustachian tube (ET) and the fibrocartilaginous tissue of the foramen lacerum after a medial maxillectomy and resection of the pterygoid plates. The main anatomical landmarks to the corresponding ICA segment include: the vidian nerve that points to the lacerum and horizontal segments, the mandibular nerve (V3) that heralds the petrous segment, the foramen ovale and the ET that signal toward the carotid canal, and the posterior trunk of the mandibular nerve (V3) and the ET that mark the parapharyngeal segment.
  
  
  CONCLUSIONS
  EEAs provide access to the ICA from its cavernous to the distal parapharyngeal segments. A stepwise approach is critical to its exposure and control. Surgeons must be aware of its frequently tortuous three-dimensional course and the intimate relation of the vessel to the carotid canal and the cartilage of the foramen lacerum.
authors.affiliation: Department of Otolaryngology, University of São Paulo, São Paulo, Brazil. fsgfortes@yahoo.com.br
authors.forename: Felipe S G
authors.initials: FS
authors.lastname: Fortes
authors.forename: Carlos D
authors.initials: CD
authors.lastname: Pinheiro-Neto
authors.forename: Ricardo L
authors.initials: RL
authors.lastname: Carrau
authors.forename: Rubens V
authors.initials: RV
authors.lastname: Brito
authors.forename: Daniel M
authors.initials: DM
authors.lastname: Prevedello
authors.forename: Luiz U
authors.initials: LU
authors.lastname: Sennes
mesh_terms: D002102:Cadaver; D002343:Carotid Artery, Internal / Q000033:anatomy & histology*; D004724:Endoscopy / Q000379:methods*; D006801:Humans; D008953:Models, Anatomic; D009296:Nasal Cavity; D015203:Reproducibility of Results