title: Jugular valve incompetence in transient global amnesia. A problem revisited.
abstract: OBJECTIVE
  Previous studies have suggested that transient global amnesia (TGA) may be provoked by cerebral venous congestion due to a reflux during Valsalva maneuver (VM) caused by internal jugular venous valve incompetence (IJVVI). We investigated the hemodynamic consequences of postural changes on IJVVI and on intracranial veins in patients with TGA and control subjects.
  
  
  METHODS
  IJVVI was assessed by means of extracranial color-coded duplex sonography during VM in 28 patients with TGA and 25 controls. The basal vein Rosenthal was examined by transcranial color-coded sonography registering flow velocities (FV) at rest and during VM. These measurements were performed in the supine and in a sitting position.
  
  
  RESULTS
  IJVVI was identified in supine position in 19/28 (68%) of TGA patients and in 7/25 (28%) of controls (P < .05). Body position had no effect on the detection of IJVVI. Intracranial venous FV at rest and during VM did neither differ between patients and controls, nor between persons with and without IJVVI.
  
  
  CONCLUSIONS
  Consistent with results of other groups, we found a significantly higher rate of IJVVI in TGA patients compared to controls. However, we found no differences of intracranial venous circulation between groups nor an effect of body position. This sheds doubt on the assumption of a causative effect of IJVVI in TGA.
authors.affiliation: Department of Neurology, Justus-Liebig University, Giessen, Germany; Department of Neurology, Krankenhaus Meran, Meran, Italy.
authors.forename: Piergiorgio
authors.initials: P
authors.lastname: Lochner
authors.forename: Max
authors.initials: M
authors.lastname: Nedelmann
authors.forename: Manfred
authors.initials: M
authors.lastname: Kaps
authors.forename: Erwin
authors.initials: E
authors.lastname: Stolz
mesh_terms: D000328:Adult; D020236:Amnesia, Transient Global / Q000175:diagnosis* / Q000209:etiology*; D005260:Female; D006801:Humans; D007601:Jugular Veins / Q000000981:diagnostic imaging*; D008297:Male; D008875:Middle Aged; D014463:Ultrasonography / Q000379:methods*; D014636:Valsalva Maneuver; D014689:Venous Insufficiency / Q000150:complications* / Q000000981:diagnostic imaging*; D055422:Venous Valves / Q000000981:diagnostic imaging*
keywords: Transient global amnesia; Valsalva maneuver; basal vein of Rosenthal; flow velocities; internal jugular venous valve incompetence