Surface Integration of Velocity Vectors from 3D Digital Colour Doppler: An Angle Independent Method for Laminar Flow Measurements

Abstract

Surface integration of velocity vectors to compute three-dimensional Doppler flow data is less angle dependent than conventional Doppler methods.

The use of live three-dimensional Doppler echocardiography in the measurement of cardiac output

“…Threedimensional echocardiographic methods of flow volume computation overcome the angle dependence of 2-D Doppler (18) and the limitations of standard 2-DE methods of volume computation. However, these studies were limited by the time-consuming acquisitions that required multiple 2-DE slices to be acquired and reconstructed into a 3-D image.…”

Real-time 3-Dimensional Doppler Echocardiography for the Assessment of Stroke Volume: An In Vivo Human Study Compared with Standard 2-Dimensional Echocardiography

“…[18][19][20][21][22] This provided an accurate method of volume calculation and has more recently been used for atrial septal defect shunt calculation. 23 This method, however, was limited by the need for time-consuming acquisition and reconstruction of multiple 2DE images.…”

Evaluation of a New 3‐Dimensional Color Doppler Flow Method to Quantify Flow Across the Mitral Valve and in the Left Ventricular Outflow Tract

“…The use of hemispheric 3D flow sampling planes has been shown to measure flow volumes independent of the angle of incidence between the ultrasound beam and the direction of blood flow. [3][4][5][6][7][8][9][10][11][12][13][15][16][17]19,22 The size and location of the sampling planes were adjusted manually at end systole to cover the cross-sectional area of color Doppler flow at sampling rates high enough to avoid aliasing. These planes were maintained throughout the simulated cardiac cycle.…”

“…1,2,11,12,[14][15][16][17][18] Also, stroke volumes have been calculated from 2D echocardiographic measurements of the subvalvular diameter and the velocity time integral of the systolic velocity at the LVOT. 2,14,16,17,19 Although 2D Doppler measurements are the most frequently used of imaging modalities in clinical medicine and investigation, they are not error free. Inaccuracies result from angle dependencies between blood flow and the ultrasound beam as well as geometric assumptions and errors in assuming a flow profile.…”

“…Inaccuracies result from angle dependencies between blood flow and the ultrasound beam as well as geometric assumptions and errors in assuming a flow profile. [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19] Three-dimensional (3D) color Doppler echocardiography has recently become available for clinical and investigational use. It does not share the limitations of 2D Doppler echocardiography because the 3D color Doppler measurement is not angle dependent and does not require geometric assumptions.…”