title: Ultrasound low-velocity flow estimations using cross-correlation and decorrelation: a thread phantom study.
abstract: In this paper, two time-domain flow velocity measurement methods, cross-correlation and decorrelation, were implemented and compared in measuring low blood-flow velocities, ranging from 0.05 to 5 cm/s, at known beam-vessel angles of 50-90 degrees in a thread phantom. Both methods achieved a significant correlation between the measured and the known velocities (r=0.99; P<0.001) in the thread phantom measurements, at 50-70 degrees beam-vessel angles. Although the cross-correlation method showed a significant correlation (r>0.99; P<0.001), this method caused large errors (>45%) at 80 degrees and 90 degrees , whereas the decorrelation method not only achieved a significant correlation (r>0.99; P<0.001) but also resulted in smaller errors (<19%) at 80 degrees and 90 degrees . This study demonstrates the potential of time-domain decorrelation method for measuring low flow velocity at large beam-vessel angles near perpendicular conditions.
authors.affiliation: Institute of Biomedical Engineering, National Yang Ming University, 155, 2nd Sec., Li-Nung St., Taipei 112, Taiwan.
authors.forename: Ton-Tai
authors.initials: TT
authors.lastname: Pan
authors.forename: Huihua Kenny
authors.initials: HK
authors.lastname: Chiang
mesh_terms: D000465:Algorithms; D001783:Blood Flow Velocity / Q000502:physiology*; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D008833:Microcirculation / Q000502:physiology*; D019047:Phantoms, Imaging; D012044:Regression Analysis; D012212:Rheology / Q000379:methods*; D013223:Statistics as Topic; D014463:Ultrasonography / Q000295:instrumentation / Q000379:methods*; D014680:Veins / Q000000981:diagnostic imaging* / Q000502:physiology*