Noninvasive simultaneous assessment of wall shear rate and wall distension in carotid arteries

Quantification of Ultrasound Correlation‐Based Flow Velocity Mapping and Edge Velocity Gradient Measurement

“…4 Using multigate Doppler measurements, the blood flow velocity profile and blood flow velocity gradient at the wall edge were determined from longitudinal (along the blood flow directions) views of blood vessels. [5][6][7][8] Dae Woo Park, PhD, Grant H. Kruger, PhD, Jonathan M. Rubin, MD, PhD, James Hamilton, PhD, Paul Gottschalk, PhD, Robert E. Dodde, PhD, Albert J. Shih, PhD, William F. Weitzel, MD Received January 1, 2013, This study investigated the use of ultrasound speckle decorrelation-and correlationbased lateral speckle-tracking methods for transverse and longitudinal blood velocity profile measurement, respectively. By studying the blood velocity gradient at the vessel wall, vascular wall shear stress, which is important in vascular physiology as well as the pathophysiologic mechanisms of vascular diseases, can be obtained.…”

Estimation of the viscoelastic properties of vessel walls using a computational model and Doppler ultrasound

“…The Doppler system (Tortoli et al, 2006) , developed at the University of Florence, consists of a PC add-on custom board based on a high-speed digital signal processor, capable of simultaneously applying pulsed wave excitation to two independent probes and processing in real-time the related echoes. One probe was perpendicularly oriented to the vessel to optimally detect the radial wall movements, while the second probe was oriented at a suitable Doppler angle to simultaneously measure the fluid velocities.…”

“…The main limitation of this approach is that it cannot track instantaneous changes in the wall properties and requires measurement over several cardiac cycles. This paper presents a noniterative technique to estimate the viscoelastic parameters of a three-element Maxwell vascular wall (Zener) model (Barnes et al, 1989) from data collected in real time by a new US Doppler system (Tortoli et al, 2006) which continuously monitors the vessel flow rate and wall displacement. Using the 3-element Zener model allows to capture fundamental viscoelastic properties of the arterial wall by including both creep and stress relaxation (Valdez-Jasso et al, 2007), while a viscoelastic model composed by only two elements would neglect one of the two phenomena.…”

Doppler Ultrasound‐Based Rheology

“…This simplifies the identification of artefacts influencing the profile shape (Jones, 1993). In addition, it is possible to use different velocity estimation approaches such as central or maximum frequency (Tortoli et al, 1995(Tortoli et al, , 1996(Tortoli et al, , 2006.…”