Duplex Doppler examination in renal disease: evaluation of vascular involvement.

Evaluation of renal disease and transplant rejection has been limited to excretory urography, nuclear isotope flow studies and other more invasive procedures. The B-scan ultrasound findings are often nonspecific. The development of duplex pulsed Doppler sonography has permitted evaluation of both arterial and venous flow. Duplex ultrasound studies in patients with a suspected diminution in renal function demonstrated the ability to delineate normal and abnormal flow, limiting the differential diagnosis, and in some cases actually documented an abnormality before gross pathologic changes became evident.