title: Positional Relations of the Cervical Vagus Nerve Revisited.
abstract: OBJECTIVE
  The cervical part of the vagus nerve (CVN) has become an important target for stimulation therapy to treat epilepsy and psychiatric conditions. For this purpose, the CVN is visualized in the carotid sheath, assuming it to be localized dorsomedially between the carotid artery (CA) and the internal jugular vein (JV). The aim of our morphological study was therefore to revisit the CVN relationships to the CA and JV, hypothesizing it to have common variations to this classical textbook anatomy.
  
  
  METHODS
  Positional relations of the CVN, CA and JV were investigated in the carotid sheath of 35 cadavers at the C3 to C6 level. Positional relations of the CVN, CA and JV were documented on the basis of a 3 × 3 chart.
  
  
  RESULTS
  Eighteen different arrangements of the CVN, CA and JV were observed. The typical topographic relationship of the CVN dorsomedially between the CA and JV was only found in 42% of all cases. The CVN was located dorsally or (dorso-)laterally to the CA in 80% and dorsally or (dorso-)medially of the JV in 96% of all cases.
  
  
  CONCLUSIONS
  Classical textbook anatomy of the CVN is only present in a minority of cases. Positional variations in contrast to textbook anatomy are considerably more frequent than previously described, which might be a hypothetical morphological explanation for the lack of efficacy or side effects of CVN stimulation. Furthermore, the position of the CVN relative to the internal jugular vein is more consistent than to the CA.
authors.affiliation: Faculty of Medicine, Department of Neurosurgery, University Clinic of Leipzig, Leipzig, Germany.|Institute of Anatomy, University of Leipzig, Leipzig, Germany.
authors.forename: Uwe
authors.initials: U
authors.lastname: Planitzer
authors.affiliation: Department of Anatomy, University of Otago, Dunedin, New Zealand.
authors.forename: Niels
authors.initials: N
authors.lastname: Hammer
authors.affiliation: Institute of Anatomy, University of Leipzig, Leipzig, Germany.
authors.forename: Ingo
authors.initials: I
authors.lastname: Bechmann
authors.affiliation: Faculty of Medicine, Department of Neurosurgery, University Clinic of Leipzig, Leipzig, Germany.
authors.forename: Juliane
authors.initials: J
authors.lastname: Glätzner
authors.affiliation: Institute of Anatomy, University of Leipzig, Leipzig, Germany.
authors.forename: Sabine
authors.initials: S
authors.lastname: Löffler
authors.affiliation: Institute of Anatomy, University of Leipzig, Leipzig, Germany.
authors.forename: Robert
authors.initials: R
authors.lastname: Möbius
authors.affiliation: Department of Anatomy, University of Kiel, Kiel, Germany.
authors.forename: Bernhard N
authors.initials: BN
authors.lastname: Tillmann
authors.affiliation: Faculty of Medicine, Department of Neurology, University Clinic of Leipzig, Leipzig, Germany.
authors.forename: David
authors.initials: D
authors.lastname: Weise
authors.affiliation: Faculty of Medicine, Department of Neurosurgery, University Clinic of Leipzig, Leipzig, Germany.
authors.forename: Dirk
authors.initials: D
authors.lastname: Winkler
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D002339:Carotid Arteries / Q000033:anatomy & histology*; D002572:Cervical Plexus / Q000033:anatomy & histology* / Q000098:blood supply; D005260:Female; D006801:Humans; D007601:Jugular Veins / Q000033:anatomy & histology*; D008297:Male; D014630:Vagus Nerve / Q000033:anatomy & histology* / Q000098:blood supply
keywords: Carotid sheath; common carotid artery; epilepsy; internal jugular vein; vagus nerve stimulation