Doppler examination of the kidney in infants and children.

Doppler sonography has become a reliable indicator of renal vascularization. Color Doppler permits mapping of regional intrarenal blood flow, as well as flow in the main renal artery and vein. The spectral display of the Doppler signal arising from the renal arteries yields valuable information about the state of the peripheral vascular bed. Our understanding of intrarenal Doppler curves has evolved from a simplistic model of pulsatility index number equals diagnosis to the more sophisticated concept that changes in these curves imply a change in the physiology of the kidney. This is a summary of current clinical applications of the Doppler technology to diseases of the kidney in the child.