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Ultrasound speckle tracking for carotid strain assessment has in the past decade gained interest in studies of arterial stiffness and cardiovascular diseases. The aim of this study was to validate and directly contrast carotid strain assessment by speckle tracking applied on clinical and high-frequency ultrasound images in vitro. Four polyvinyl alcohol phantoms mimicking the carotid artery were constructed with different mechanical properties and connected to a pump generating carotid flow profiles. Gray-scale ultrasound long- and short-axis images of the phantoms were obtained using a standard clinical ultrasound system, Vivid 7 (GE Healthcare, Horten, Norway) and a high-frequency ultrasound system, Vevo 2100 (FUJIFILM, VisualSonics, Toronto, Canada) with linear-array transducers (12L/MS250). Radial, longitudinal and circumferential strains were estimated using an in-house speckle tracking algorithm and compared with reference strain acquired by sonomicrometry. Overall, the estimated strain corresponded well with the reference strain. The correlation between estimated peak strain in clinical ultrasound images and reference strain was 0.91 (p

The detection of changes in the properties of the walls in blood vessels (e.g. modifications in thickness or elasticity) is a promising way for the early diagnosis of cardiovascular diseases (e.g. atherosclerosis), and some attempts have been made using classic ultrasonic images. However, to obtain a reliable non-invasive estimation of these changes still presents many challenges that must be overcome, in particular, to achieve an accurate estimation of the vessel wall thickness, which usually is associated to strain and elasticity alterations happening before the cardiovascular disease presents clinical symptom; to solve efficiently these aspects is a very difficult task. In this work, the application to vessels of a recent ultrasonic method developed by the authors for estimating wall thicknesses is described. This method (based on high-resolution power spectral density - PSD) and its algorithmic responses were tested on an arterial phantom under physiological conditions of flow and pressure, and some results are compared to those obtained using a direct-time thickness estimation and with the resolutions related to our alternative cross-correlation option shown in previous papers. A higher spatial resolution is obtained, for experimental multi-pulse ultrasonic echoes, with this PSD method in comparison to those based on conventional echography, cross correlation operators or other spectral options.