Impact of velocity distribution assumption on simplified laser speckle imaging equation.

نویسندگان

  • Julio C Ramirez-San-Juan
  • Ruben Ramos-García
  • Ileana Guizar-Iturbide
  • Gabriel Martínez-Niconoff
  • Bernard Choi
چکیده

Since blood flow is tightly coupled to the health status of biological tissue, several instruments have been developed to monitor blood flow and perfusion dynamics. One such instrument is laser speckle imaging. The goal of this study was to evaluate the use of two velocity distribution assumptions (Lorentzian- and Gaussian-based) to calculate speckle flow index (SFI) values. When the normalized autocorrelation function for the Lorentzian and Gaussian velocity distributions satisfy the same definition of correlation time, then the same velocity range is predicted for low speckle contrast (0 < C < 0.6) and predict different flow velocity range for high contrast. Our derived equations form the basis for simplified calculations of SFI values.

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عنوان ژورنال:
  • Optics express

دوره 16 5  شماره 

صفحات  -

تاریخ انتشار 2008