title: Utility of transcranial Doppler ultrasound for the integrative assessment of cerebrovascular function.
abstract: There is considerable utility in the use of transcranial Doppler ultrasound (TCD) to assess cerebrovascular function. The brain is unique in its high energy and oxygen demand but limited capacity for energy storage that necessitates an effective means of regional blood delivery. The relative low cost, ease-of-use, non-invasiveness, and excellent temporal resolution of TCD make it an ideal tool for the examination of cerebrovascular function in both research and clinical settings. TCD is an efficient tool to access blood velocities within the cerebral vessels, cerebral autoregulation, cerebrovascular reactivity to CO(2), and neurovascular coupling, in both physiological states and in pathological conditions such as stroke and head trauma. In this review, we provide: (1) an overview of TCD methodology with respect to other techniques; (2) a methodological synopsis of the cerebrovascular exam using TCD; (3) an overview of the physiological mechanisms involved in regulation of the cerebral blood flow; (4) the utility of TCD for assessment of cerebrovascular pathology; and (5) recommendations for the assessment of four critical and complimentary aspects of cerebrovascular function: intra-cranial blood flow velocity, cerebral autoregulation, cerebral reactivity, and neurovascular coupling. The integration of these regulatory mechanisms from an integrated systems perspective is discussed, and future research directions are explored.
authors.affiliation: Department of Human Kinetics, Faculty of Health and Social Development, University of British Columbia Okanagan, 3333 University Way, Kelowna, BC, Canada V1V 1V7. ckwillie@gmail.com
authors.forename: C K
authors.initials: CK
authors.lastname: Willie
authors.forename: F L
authors.initials: FL
authors.lastname: Colino
authors.forename: D M
authors.initials: DM
authors.lastname: Bailey
authors.forename: Y C
authors.initials: YC
authors.lastname: Tzeng
authors.forename: G
authors.initials: G
authors.lastname: Binsted
authors.forename: L W
authors.initials: LW
authors.lastname: Jones
authors.forename: M J
authors.initials: MJ
authors.lastname: Haykowsky
authors.forename: J
authors.initials: J
authors.lastname: Bellapart
authors.forename: S
authors.initials: S
authors.lastname: Ogoh
authors.forename: K J
authors.initials: KJ
authors.lastname: Smith
authors.forename: J D
authors.initials: JD
authors.lastname: Smirl
authors.forename: T A
authors.initials: TA
authors.lastname: Day
authors.forename: S J
authors.initials: SJ
authors.lastname: Lucas
authors.forename: L K
authors.initials: LK
authors.lastname: Eller
authors.forename: P N
authors.initials: PN
authors.lastname: Ainslie
mesh_terms: D001921:Brain / Q000098:blood supply / Q000502:physiology; D002536:Cerebral Arteries / Q000000981:diagnostic imaging / Q000503:physiopathology; D002560:Cerebrovascular Circulation / Q000502:physiology*; D002561:Cerebrovascular Disorders / Q000175:diagnosis / Q000503:physiopathology*; D006801:Humans; D008959:Models, Neurological; D017585:Ultrasonography, Doppler, Transcranial / Q000295:instrumentation / Q000379:methods*