title: Shear wave speed measurement using an unfocused ultrasound beam.
abstract: Tissue elasticity is related to pathology and, therefore, has important medical applications. Radiation force from a focused ultrasound beam has been used to produce shear waves in tissues for shear wave speed and tissue elasticity measurements. The feasibility of shear wave speed measurement using radiation force for an unfocused ultrasound beam is demonstrated in this study with a linear and a curved array transducer. Consistent measurement of shear wave speed was achieved over a relatively long axial extent (z = 10-40 mm for the linear array, and z = 15-60 mm for the curved array) in three calibrated phantoms with different shear moduli. In vivo measurements on the biceps of a healthy volunteer show consistent increase of shear wave speed for the biceps under 0, 1, 2 and 3 kg loading. Advantages and limitations of unfocused push are discussed.
authors: Department of Physiology and Biomedical Engineering, Mayo Clinic College of Medicine,200 First Street SW, Rochester, MN 55905, USA.
authors: Heng
authors: H
authors: Zhao
authors: Pengfei
authors: P
authors: Song
authors: Matthew W
authors: MW
authors: Urban
authors: James F
authors: JF
authors: Greenleaf
authors: Shigao
authors: S
authors: Chen
mesh_terms: D000162:Acoustics; D000704:Analysis of Variance; D055119:Elastic Modulus; D054459:Elasticity Imaging Techniques / Q000379:methods*; D005240:Feasibility Studies; D006801:Humans; D016014:Linear Models; D018482:Muscle, Skeletal / Q000000981:diagnostic imaging*; D019047:Phantoms, Imaging; D014159:Transducers