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文章來源: 於 2005-04-20 15:16:15

Color flow imaging (CFI) is a variation of pulsed-wave (PW) Doppler, in which colors represent the velocity and direction of blood flow. The colors superimposed on the 2-D echocardiographic anatomy, produce a real-time representation of the spatial extent of blood flow. Imaging with CFI allows you to find blood flow quicker and easier than with conventional pulsed-wave (PW) or continuous-wave (CW) Doppler.

Color Flow Imaging helps:

  • Position PW and CW Doppler beams
  • Detect multiple jets, simultaneously
  • Identify areas of non-laminar blood flow
  • Detect and partially quantify regurgitant and shunt flows
  • Reduce the time required to examine complex blood flow patterns

While CFI has many advantages over conventional Doppler, it does have some limitations. You will need a complete understanding of both to obtain accurate blood flow information

This tutorial, divided into three sections, presents both the advantages and limitations of CFI:

  • Color Flow Imaging Basics discusses using color flow images to identify blood flow.
  • Factors Affecting Color Flow Images describes some of the technical factors influencing the color, sensitivity, and accuracy of the image you see.
  • Blood Flow Patterns in the Heart presents examples of normal and abnormal blood flow patterns.

Color Flow Imaging Basics


PW Doppler and CFI share some advantages and limitations. Both techniques:

  • provide information on blood flow direction and velocity.
  • can distinguish laminar from turbulent blood flow.
  • are subject to aliasing.

This section describes how to derive this basic information from a color flow image and, in addition, reviews some helpful color flow scanning techniques.


module230_c001.jpg

Apical four-chamber view showing normal blood flow moving through the mitral valve in diastole.
module230_c002.jpg

An image demonstrating normal systolic left ventricular outflow tract (LVOT) flow from the apical five-chamber view.