title: Comparative sonographic study of cerebral hemodynamic differences and changes after oxygen therapy in healthy youths of different ethnicities in Tibet.
abstract: OBJECTIVE
  The purpose of this study was to sonographically assess the cerebral hemodynamic differences and changes after oxygen therapy in healthy youths of different ethnicities in Tibet.
  
  
  METHODS
  Sixty-six healthy young Han visitors and 29 healthy young Tibetan residents were divided into 4 groups. Basic information was collected. Pulsed Doppler sonography was used to record the cerebral hemodynamic parameters for the internal carotid, vertebral, and middle cerebral arteries. The participants were then instructed to inhale oxygen, and basic information and cerebral hemodynamic parameters were recorded at 1, 2, 4, and 8 minutes, respectively. Differences in these parameters between groups were analyzed.
  
  
  RESULTS
  In comparisons of the flow parameters between sex-matched groups, the mean resistive index values for the internal carotid, vertebral, and middle cerebral arteries in the Han groups were significantly lower than those in the Tibetan groups (P <. 05). The mean peak systolic velocity, end-diastolic velocity, and mean velocity values for the middle cerebral artery in the Han groups were significantly higher than those in the Tibetan groups (P < .05). After oxygen uptake, there were no significant differences in the mean arterial oxygen saturation, heart rate, mean velocity, and resistive index values between the male groups, and similar changes were found for the arterial oxygen saturation and peak systolic velocity values between female groups after 8 minutes of oxygen uptake (P > .05).
  
  
  CONCLUSIONS
  Sonography is a useful modality for noninvasive and real-time detection of changes in cerebral hemodynamics and can provide reference values for the prevention and treatment of cerebrovascular diseases.
authors.affiliation: Department of Ultrasound Diagnostics, Tangdu Hospital, Fourth Military Medical University, Xi'an, China (J.W., L.J.Y., Y.Y.D.); and Department of Special Examination, Tibet Corps Hospital, Chinese People's Armed Police Forces, Lhasa, China (S.Z.X., Y.Z., C.F.B.).
authors.forename: Jia
authors.initials: J
authors.lastname: Wang
authors.affiliation: Department of Ultrasound Diagnostics, Tangdu Hospital, Fourth Military Medical University, Xi'an, China (J.W., L.J.Y., Y.Y.D.); and Department of Special Examination, Tibet Corps Hospital, Chinese People's Armed Police Forces, Lhasa, China (S.Z.X., Y.Z., C.F.B.). xsz1952@163.com duanyy@fmmu.edu.cn.
authors.forename: Shu Zhen
authors.initials: SZ
authors.lastname: Xu
authors.affiliation: Department of Ultrasound Diagnostics, Tangdu Hospital, Fourth Military Medical University, Xi'an, China (J.W., L.J.Y., Y.Y.D.); and Department of Special Examination, Tibet Corps Hospital, Chinese People's Armed Police Forces, Lhasa, China (S.Z.X., Y.Z., C.F.B.).
authors.forename: Yong
authors.initials: Y
authors.lastname: Zha
authors.affiliation: Department of Ultrasound Diagnostics, Tangdu Hospital, Fourth Military Medical University, Xi'an, China (J.W., L.J.Y., Y.Y.D.); and Department of Special Examination, Tibet Corps Hospital, Chinese People's Armed Police Forces, Lhasa, China (S.Z.X., Y.Z., C.F.B.).
authors.forename: Ciugene F
authors.initials: CF
authors.lastname: Bbu
authors.affiliation: Department of Ultrasound Diagnostics, Tangdu Hospital, Fourth Military Medical University, Xi'an, China (J.W., L.J.Y., Y.Y.D.); and Department of Special Examination, Tibet Corps Hospital, Chinese People's Armed Police Forces, Lhasa, China (S.Z.X., Y.Z., C.F.B.).
authors.forename: Li Jun Yuan
authors.initials: LJ
authors.lastname: Li
authors.affiliation: Department of Ultrasound Diagnostics, Tangdu Hospital, Fourth Military Medical University, Xi'an, China (J.W., L.J.Y., Y.Y.D.); and Department of Special Examination, Tibet Corps Hospital, Chinese People's Armed Police Forces, Lhasa, China (S.Z.X., Y.Z., C.F.B.).
authors.forename: Yun You
authors.initials: YY
authors.lastname: Duan
mesh_terms: D000293:Adolescent; D001929:Brain Edema / Q000000981:diagnostic imaging / Q000503:physiopathology; D002343:Carotid Artery, Internal / Q000000981:diagnostic imaging / Q000503:physiopathology; D002560:Cerebrovascular Circulation; D005006:Ethnicity; D005260:Female; D006439:Hemodynamics; D006801:Humans; D008297:Male; D020768:Middle Cerebral Artery / Q000000981:diagnostic imaging / Q000503:physiopathology; D010102:Oxygen Inhalation Therapy; D018609:Tibet; D018617:Ultrasonography, Doppler, Pulsed; D017585:Ultrasonography, Doppler, Transcranial; D014711:Vertebral Artery / Q000000981:diagnostic imaging / Q000503:physiopathology; D055815:Young Adult
keywords: cerebral vessels; hemodynamic; hypoxia; oxygen therapy; plateau; sonography; vascular ultrasound