title: Involvement of jugular valve insufficiency in cerebral venous air embolism.
abstract: BACKGROUND
  Cerebral venous air entrapment is a rare finding on cranial computed tomography (CT) scan. Peripheral air embolism is discussed as a potential cause. However, the mechanism of retrograde passage through internal jugular valves and veins is unclear.
  
  
  METHODS
  The case of a patient is reported, who had air entrapment in the left cavernous sinus. Prior to CT scanning, a peripheral intravenous line had been placed. Ultrasound revealed excessive insufficiency of the left internal jugular valve. To further study the mechanism of embolism, an echo contrast agent was injected into the cubital vein. A Valsalva maneuver resulted in retrograde transition of microbubbles across the insufficient valve. Valvular function on the unaffected right side was intact.
  
  
  CONCLUSIONS
  This case report gives insight into the mechanism of cerebral venous air embolism. This is the firstcase describing jugular valve insufficiency as the missing link between peripheral air embolism and cerebral venous air entrapment.
authors.affiliation: Department of Neurology, Johannes Gutenberg University, Mainz, Germany. mnedelma@uni-mainz.de
authors.forename: Max
authors.initials: M
authors.lastname: Nedelmann
authors.forename: Patrick
authors.initials: P
authors.lastname: Pittermann
authors.forename: Klaus Kurt
authors.initials: KK
authors.lastname: Gast
authors.forename: Wibke
authors.initials: W
authors.lastname: Mueller-Forell
authors.forename: Marianne
authors.initials: M
authors.lastname: Dieterich
mesh_terms: D000328:Adult; D003937:Diagnosis, Differential; D004618:Embolism, Air / Q000175:diagnosis / Q000209:etiology*; D005260:Female; D006801:Humans; D007601:Jugular Veins / Q000503:physiopathology*; D012852:Sinusitis / Q000175:diagnosis / Q000188:drug therapy; D014057:Tomography, X-Ray Computed; D017585:Ultrasonography, Doppler, Transcranial; D014689:Venous Insufficiency / Q000150:complications* / Q000175:diagnosis / Q000503:physiopathology*