Two-dimensional (2D) color Doppler flow mapping (CDFM) of the flow convergence (FC) region provides important information on regurgitant volumes. However, the 2D view provided by CDFM may not reveal complete FC information especially for complex orifice geometries. We used a Toshiba ultrasound scanner (Nyquist limits (NL): 10 - 60 cm/sec) interfaced to a Tomtec 3D ultrasound reconstruction computer which provides multiple views of structure and flow, to visualize the FC region for pulsatile flow (20 - 90 cc/beat; 50 - 80 bpm) through a variety of orifice sizes (0.1 cm2 - 2.0 cm2) and shapes(circular, oval, Y-shaped). The FC region could be clearly visualized using 3D ultrasound Doppler flow imaging for all hemodynamic conditions at all NL's. Aliasing radii measured from the 3D flow images correlated well with actual flow volumes (y=0.05 x+0.21; r=0.98, NL= 38cm/sec) with best results obtained at intermediate (30 - 50 cm/sec) NL's. Increasing orifice size and decreasing flow rate both caused perceptible flattening of the 3D FC contour within the central convergence region where angle induced velocity errors are minimal. 3D ultrasound flow imaging of the proximal flow convergence region presents both qualitative and quantitative advantages over conventional 2D CDFM and should improve clinical application of this technique.