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Keywords:

  • Transient global amnesia;
  • internal jugular venous valve incompetence;
  • basal vein of Rosenthal;
  • Valsalva maneuver;
  • flow velocities

ABSTRACT

BACKGROUND AND PURPOSE

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.

MATERIALS AND 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.