title: Investigation of Ultrasound-Measured Flow Velocity, Flow Rate and Wall Shear Rate in Radial and Ulnar Arteries Using Simulation.
abstract: Parameters of blood flow measured by ultrasound in radial and ulnar arteries, such as flow velocity, flow rate and wall shear rate, are widely used in clinical practice and clinical research. Investigation of these measurements is useful for evaluating accuracy and providing knowledge of error sources. A method for simulating the spectral Doppler ultrasound measurement process was developed with computational fluid dynamics providing flow-field data. Specific scanning factors were adjusted to investigate their influence on estimation of the maximum velocity waveform, and flow rate and wall shear rate were derived using the Womersley equation. The overestimation in maximum velocity increases greatly (peak systolic from about 10% to 30%, time-averaged from about 30% to 50%) when the beam-vessel angle is changed from 30° to 70°. The Womersley equation was able to estimate flow rate in both arteries with less than 3% error, but performed better in the radial artery (2.3% overestimation) than the ulnar artery (15.4% underestimation) in estimating wall shear rate. It is concluded that measurements of flow parameters in the radial and ulnar arteries with clinical ultrasound scanners are prone to clinically significant errors.
authors.affiliation: School of Science and Engineering, University of Dundee, Dundee, United Kingdom.
authors.forename: Xiaowei
authors.initials: X
authors.lastname: Zhou
authors.affiliation: School of Mechanical and Power Engineering, East China University of Science and Technology, Shanghai, China; NHS Tayside Medical Physics, Ninewells Hospital, Dundee, United Kingdom.
authors.forename: Chunming
authors.initials: C
authors.lastname: Xia
authors.affiliation: School of Mechanical and Power Engineering, East China University of Science and Technology, Shanghai, China; NHS Tayside Medical Physics, Ninewells Hospital, Dundee, United Kingdom.
authors.forename: Gandy
authors.initials: G
authors.lastname: Stephen
authors.affiliation: Cardiovascular and Diabetes Medicine, Ninewells Hospital and Medical School, University of Dundee, Dundee, United Kingdom.
authors.forename: Faisel
authors.initials: F
authors.lastname: Khan
authors.affiliation: School of Science and Engineering, University of Dundee, Dundee, United Kingdom.
authors.forename: George A
authors.initials: GA
authors.lastname: Corner
authors.affiliation: Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, United Kingdom.
authors.forename: Peter R
authors.initials: PR
authors.lastname: Hoskins
authors.affiliation: School of Science and Engineering, University of Dundee, Dundee, United Kingdom. Electronic address: z.y.huang@dundee.ac.uk.
authors.forename: Zhihong
authors.initials: Z
authors.lastname: Huang
mesh_terms: D000328:Adult; D001783:Blood Flow Velocity / Q000502:physiology; D003198:Computer Simulation; D006801:Humans; D008297:Male; D017534:Radial Artery / Q000000981:diagnostic imaging / Q000502:physiology*; D013314:Stress, Mechanical; D017535:Ulnar Artery / Q000000981:diagnostic imaging / Q000502:physiology*; D014463:Ultrasonography / Q000379:methods*
keywords: Computational fluid dynamics; Doppler ultrasound; Field II; Flow rate; Flow velocity; Radial artery; Simulation; Ulnar artery; Wall shear rate; Womersley