title: Assessment of the calf vein cross section change during stand-test after a 90 day bed rest by echography.
abstract: OBJECTIVE
  To evaluate the contribution of the calf veins distension during stand test to orthostatic intolerance (OI).
  
  
  METHODS
  The population consisted of a control group (Co, n=9) and an exercise (Fly-Wheel) counter-measure group (CM, n=9). Calf vein cross section area was assessed by echography during pre and post HDT stand-tests.
  
  
  RESULTS
  Tibial, and muscular vein section at rest did not change during HDT in both groups. From supine to standing, the Tibial and muscular vein section increased significantly more at post HDT in non tolerant subjects, compare to pre HDT (tibial V: +122% from pre-HDT, muscular V: +145% p<005). In tolerant subjects the vein cross section increase from supine to stand was similar pre and post HDT.
  
  
  CONCLUSIONS
  Fly-Wheel CM, did not reduce OI. High calf vein section increase at post-HDT stand-test compare to pre-HDT was significantly correlated with OI but not with CM.
authors.forename: A
authors.initials: A
authors.lastname: Capri
authors.forename: P
authors.initials: P
authors.lastname: Kerbeci
authors.forename: L
authors.initials: L
authors.lastname: Pascaud
authors.forename: Ph
authors.initials: P
authors.lastname: Arbeille
mesh_terms: D000328:Adult; D001510:Bed Rest; D015444:Exercise / Q000502:physiology*; D018475:Head-Down Tilt; D006801:Humans; D007024:Hypotension, Orthostatic / Q000000981:diagnostic imaging / Q000503:physiopathology*; D007866:Leg / Q000098:blood supply* / Q000000981:diagnostic imaging*; D008297:Male; D011187:Posture / Q000502:physiology*; D016683:Supine Position; D018667:Tilt-Table Test; D014463:Ultrasonography; D014680:Veins / Q000502:physiology; D018544:Weightlessness Countermeasures