Doppler ultrasound in renal disease: not quite "the answer to a maiden's prayer".

Initial wild enthusiasm for the use of Doppler ultrasound in renal disease, particularly in renal transplants, led to claims that Doppler would enable diagnosis of various abnormalities without recourse to more invasive techniques. These claims have not been borne out by a more reasoned and scientific assessment of the role of Doppler ultrasound in the diagnosis of native and transplant kidney dysfunction. With the realization that changes in the Doppler findings merely reflect changes in renal blood flow induced by a variety of pathological processes has come a better understanding of how Doppler may be of benefit in the diagnosis and monitoring of these processes. The combination of duplex Doppler and color flow mapping with conventional B-mode ultrasound allows acquisition of both physiological and morphological information entirely non-invasively. Doppler ultrasound may not quite be "the answer to a maiden's prayer" in the evaluation of kidney disease but nevertheless represents a very useful tool in the nephrologist's investigative armamentarium, a tool which may be used repeatedly without detriment or risk to the patient.