Journal of Ultrasound in Medicine, Vol 11, Issue 12 647-651, Copyright © 1992 by American Institute of Ultrasound in Medicine
Intrarenal Doppler: characteristics of aging kidneys
J. D. Terry, J. A. Rysavy and M. P. Frick
Section of Radiology, Creighton University Medical Center, Omaha, Nebraska 68131.
The normal range of Doppler findings in native kidneys has not been studied
extensively. This study correlates changes in Doppler resistive index (RI)
with age in patients without renal risk factors or renal disease. Young and
old patients demonstrated the highest RI values (age < 1, mean RI =
0.73; age > 59, RI = 0.68), and patients in the 20-39 year age group
showed the lowest values (RI = 0.59). The mean RI for all ages was 0.63.
The cause of this variability is unknown. We suggest that age-related
changes in Doppler values should be considered in the interpretation of
renal Doppler measurements.