title: Variability in the Cross-Sectional Area and Narrowing of the Internal Jugular Vein in Patients Without Multiple Sclerosis.
abstract: OBJECTIVE
  Chronic cerebrospinal vascular insufficiency is a proposed condition of intraluminal stenosis of the internal jugular vein (IJV) that impedes venous flow from the brain. Calculations of IJV stenosis are vague and described in veins with at least a 50% reduction in IJV caliber at a specific level. The purpose of this study was to assess normal changes in anatomic caliber of the course of the IJV in a generalized population.
  
  
  METHODS
  Images from 500 consecutive contrast-enhanced neck CT studies performed in January-July 2011 were reviewed. Cross-sectional areas of the IJV were calculated at the jugular foramen, C1-C7 levels, and jugular angles bilaterally. Patients were excluded if they had severely motion-limited studies; limited clinical data; a history of multiple sclerosis, neck mass, or neck dissection; or known IJV occlusion. Normalized IJV cross-sectional areas at each level were compared with an averaged normalized cross-sectional area from all patients at each level.
  
  
  RESULTS
  Greater than 50% narrowing compared with a normalized average was found in 133 of 363 patients (36.6%) and was seen at all IJV levels. In 36.1% of patients this narrowing occurred at the C1 level. Most of the areas of narrowing greater than 50% occurred above the C4 level.
  
  
  CONCLUSIONS
  The IJV has marked variability in its course in the neck. Areas of narrowing greater than 50% occur most commonly in the upper cervical and skull base regions. Given the normal anatomic variations in IJV caliber, caution should be used when making the diagnosis of and treating IJV stenosis.
authors.affiliation: 1 Department of Radiology, Boston Medical Center, Boston University School of Medicine, 820 Harrison Ave, FGH Bldg, 3rd Fl, Boston, MA 02118.
authors.forename: Karen
authors.initials: K
authors.lastname: Buch
authors.affiliation: 1 Department of Radiology, Boston Medical Center, Boston University School of Medicine, 820 Harrison Ave, FGH Bldg, 3rd Fl, Boston, MA 02118.
authors.forename: Raymond
authors.initials: R
authors.lastname: Groller
authors.affiliation: 1 Department of Radiology, Boston Medical Center, Boston University School of Medicine, 820 Harrison Ave, FGH Bldg, 3rd Fl, Boston, MA 02118.
authors.forename: Rohini N
authors.initials: RN
authors.lastname: Nadgir
authors.affiliation: 1 Department of Radiology, Boston Medical Center, Boston University School of Medicine, 820 Harrison Ave, FGH Bldg, 3rd Fl, Boston, MA 02118.
authors.forename: Akifumi
authors.initials: A
authors.lastname: Fujita
authors.affiliation: 1 Department of Radiology, Boston Medical Center, Boston University School of Medicine, 820 Harrison Ave, FGH Bldg, 3rd Fl, Boston, MA 02118.|2 Department of Radiation Oncology, Boston Medical Center, Boston University School of Medicine, Boston, MA.
authors.forename: Muhammad M
authors.initials: MM
authors.lastname: Qureshi
authors.affiliation: 1 Department of Radiology, Boston Medical Center, Boston University School of Medicine, 820 Harrison Ave, FGH Bldg, 3rd Fl, Boston, MA 02118.|2 Department of Radiation Oncology, Boston Medical Center, Boston University School of Medicine, Boston, MA.|3 Department of Otolaryngology-Head and Neck Surgery, Boston Medical Center, Boston University School of Medicine, Boston, MA.
authors.forename: Osamu
authors.initials: O
authors.lastname: Sakai
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D019412:Anatomy, Cross-Sectional; D002648:Child; D002675:Child, Preschool; D003251:Constriction, Pathologic / Q000000981:diagnostic imaging*; D003287:Contrast Media; D005260:Female; D006801:Humans; D007601:Jugular Veins / Q000033:anatomy & histology / Q000000981:diagnostic imaging*; D008297:Male; D008875:Middle Aged; D009103:Multiple Sclerosis; D009333:Neck; D010690:Phlebography; D012016:Reference Values; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed; D014689:Venous Insufficiency / Q000000981:diagnostic imaging*; D055815:Young Adult
chemical_list: D003287:Contrast Media
keywords: CT; anatomy; internal jugular vein; measurement