Fig. 8

Velocity generated by VFM along an arc at each echo depth with a combination of single laminar flow and vortex flows. Colour Doppler flow data are separated into basic and vortex flow components so that vortex flow component is bilaterally symmetrical on each arc. At a given pixel, colour Doppler velocity u along the beam line is a sum of its vortex flow component \(u_{v}\) and basic flow component \(u_{b}\). The vortex flow component consists of colour Doppler velocity \(u_{v}\) and radial velocity \(v_{v}\). Likewise, the basic flow component consists of colour Doppler velocity \(u_{b}\) and radial velocity \(v_{b}\). Flow vector is the sum of flow vectors of basic and vortex flow components