Fig. (2.3d)
It shows a LS of the left kidney with a stone upper calyx (arrow) as echo-
dense focus casting posterior acoustic shadow.
(Fig. 2.4)
Doppler US of a case with renal artery stenosis, it shows Damped wave
form with marked delay in the systolic rise time, a reduction in the
pulsatility index with low flow velocities (Parvus tradus pattern).
Sampling was from an intrarenal vessel.