title: Speckle decorrelation flow measurement with B-mode US of contrast agent flow in a phantom and in rabbit kidney.
abstract: OBJECTIVE
  To use speckle decorrelation in the presence of ultrasonographic (US) contrast agent as an alternative flow measurement technique to Doppler US.
  
  
  METHODS
  In vivo and in vitro studies were performed. A tube with flowing saline solution containing contrast agent was positioned horizontally across a US image. The amount of decorrelation between a series of images was recorded. The flow profile across the tube was generated by averaging the decorrelation values and was compared with a Doppler frequency shift image. In addition, B-mode images of six rabbit kidneys were obtained during and after intravenous injection of contrast agent. Images were analyzed to compute the correlation between successive points in time.
  
  
  RESULTS
  The velocity profiles across the tube were parabolic, with the fastest flow rates measured in the center of the tube. In the rabbit kidneys, measurements indicated the largest decorrelation rates occurred in the larger vessels. The cortical decorrelation rates were significantly slower than those for the hilar vessels (P < .05) and were relatively angle independent.
  
  
  CONCLUSIONS
  Decorrelation flow measurements can be used to estimate flow in vitro and in vivo similar to measurements obtained with Doppler US but with less angle dependence. These measurements could lead to a US perfusion technique.
authors.affiliation: Department of Radiology, University of Michigan Hospitals, Ann Arbor 48109-0553, USA. jrubin@umich.edu
authors.forename: J M
authors.initials: JM
authors.lastname: Rubin
authors.forename: J B
authors.initials: JB
authors.lastname: Fowlkes
authors.forename: T A
authors.initials: TA
authors.lastname: Tuthill
authors.forename: A P
authors.initials: AP
authors.lastname: Moskalik
authors.forename: R T
authors.initials: RT
authors.lastname: Rhee
authors.forename: R S
authors.initials: RS
authors.lastname: Adler
authors.forename: S N
authors.initials: SN
authors.lastname: Kazanjian
authors.forename: P L
authors.initials: PL
authors.lastname: Carson
mesh_terms: D000818:Animals; D003287:Contrast Media; D007668:Kidney / Q000000981:diagnostic imaging*; D008954:Models, Biological; D011817:Rabbits; D012212:Rheology / Q000379:methods*; D018608:Ultrasonography, Doppler / Q000379:methods*
chemical_list: D003287:Contrast Media