title: Ultrasound imaging velocimetry: effect of beam sweeping on velocity estimation.
abstract: As an emerging flow-mapping tool that can penetrate deep into optically opaque media such as human tissue, ultrasound imaging velocimetry has promise in various clinical applications. Previous studies have shown that errors occur in velocity estimation, but the causes have not been well characterised. In this study, the error in velocity estimation resulting from ultrasound beam sweeping in image acquisition is quantitatively investigated. The effects on velocity estimation of the speed and direction of beam sweeping relative to those of the flow are studied through simulation and experiment. The results indicate that a relative error in velocity estimation of up to 20% can be expected. Correction methods to reduce the errors under steady flow conditions are proposed and evaluated. Errors in flow estimation under unsteady flow are discussed.
authors.affiliation: Institute of Space Science and Technology, Southeast University, Nanjing, China.
authors.forename: Bin
authors.initials: B
authors.lastname: Zhou
authors.forename: Katharine H
authors.initials: KH
authors.lastname: Fraser
authors.forename: Christian
authors.initials: C
authors.lastname: Poelma
authors.forename: Jean-Martial
authors.initials: JM
authors.lastname: Mari
authors.forename: Robert J
authors.initials: RJ
authors.lastname: Eckersley
authors.forename: Peter D
authors.initials: PD
authors.lastname: Weinberg
authors.forename: Meng-Xing
authors.initials: MX
authors.lastname: Tang
mesh_terms: D000465:Algorithms; D000818:Animals; D001783:Blood Flow Velocity / Q000502:physiology*; D001808:Blood Vessels / Q000000981:diagnostic imaging* / Q000502:physiology*; D003198:Computer Simulation; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D008955:Models, Cardiovascular; D015203:Reproducibility of Results; D012212:Rheology / Q000379:methods*; D012680:Sensitivity and Specificity; D018608:Ultrasonography, Doppler / Q000379:methods*
keywords: Cardiovascular flow; Doppler; Flow measurement; Microbubble contrast agents; Particle image velocimetry; Ultrasound imaging; Wall shear stress