title: Ultrasound speckle tracking strain estimation of in vivo carotid artery plaque with in vitro sonomicrometry validation.
abstract: Our objective was to validate a previously developed speckle tracking (ST) algorithm to assess strain in common carotid artery plaques. Radial and longitudinal strain was measured in common carotid artery gel phantoms with a plaque-mimicking inclusion using an in-house ST algorithm and sonomicrometry. Moreover, plaque strain by ST for seven patients (77 ± 6 y) with carotid atherosclerosis was compared with a quantitative visual assessment by two experienced physicians. In vitro, good correlation existed between ST and sonomicrometry peak strains, both radially (r = 0.96, p < 0.001) and longitudinally (r = 0.75, p < 0.01). In vivo, greater pulse pressure-adjusted radial and longitudinal strains were found in echolucent plaques than in echogenic plaques. This illustrates the feasibility of ultrasound ST strain estimation in plaques and the possibility of characterizing plaques using ST strain in vivo.
authors.affiliation: Department of Medical Engineering, School of Technology and Health, KTH Royal Institute of Technology, Stockholm, Sweden. Electronic address: erik.widman@sth.kth.se.
authors.forename: Erik
authors.initials: E
authors.lastname: Widman
authors.affiliation: Department of Molecular Medicine and Surgery, Karolinska Institutet, Stockholm, Sweden.
authors.forename: Kenneth
authors.initials: K
authors.lastname: Caidahl
authors.affiliation: Cardiovascular Imaging & Dynamics, Department of Cardiovascular Sciences, KU Leuven, Leuven, Belgium.
authors.forename: Brecht
authors.initials: B
authors.lastname: Heyde
authors.affiliation: Cardiovascular Imaging & Dynamics, Department of Cardiovascular Sciences, KU Leuven, Leuven, Belgium.
authors.forename: Jan
authors.initials: J
authors.lastname: D'hooge
authors.affiliation: Department of Medical Engineering, School of Technology and Health, KTH Royal Institute of Technology, Stockholm, Sweden; Cardiovascular Imaging & Dynamics, Department of Cardiovascular Sciences, KU Leuven, Leuven, Belgium.
authors.forename: Matilda
authors.initials: M
authors.lastname: Larsson
mesh_terms: D000465:Algorithms; D016893:Carotid Stenosis / Q000000981:diagnostic imaging* / Q000503:physiopathology*; D055119:Elastic Modulus; D054459:Elasticity Imaging Techniques / Q000295:instrumentation / Q000379:methods*; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D019047:Phantoms, Imaging; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013314:Stress, Mechanical
keywords: Carotid artery; In vitro; In vivo; Phantom; Plaque characterization; Speckle tracking; Strain; Ultrasound; Validation