Stenosis of the accessory renal artery: Doppler ultrasound findings.

Stenosis of an accessory renal artery has been cited as a significant source of false-negative results with conventional renal artery Duplex sonography in the investigation of renal artery stenosis. Two case reports of accessory renal artery stenosis that were detectable using the newer intrarenal Doppler ultrasound technique with sampling from both poles and the hilum are presented. The cases illustrate a further advantage of Doppler ultrasound of the intrarenal arteries over the conventional technique.