Experimental study
Quantification of renal blood flow with contrast-enhanced ultrasound☆

https://doi.org/10.1016/S0735-1097(00)01210-9Get rights and content
Under an Elsevier user license
open archive

Abstract

OBJECTIVES

The goal of this study was to determine the ability of contrast-enhanced ultrasound (CEU) to quantify renal tissue perfusion.

BACKGROUND

The kinetics of tracers used to assess renal perfusion are often complicated by countercurrent exchange, tubular transport or glomerular filtration. We hypothesized that, because gas-filled microbubbles are pure intravascular tracers with a rheology similar to that of red blood cells, CEU could be used to quantify renal tissue perfusion.

METHODS

During a continuous venous infusion of microbubbles (SonoVue), regional renal perfusion was quantified in nine dogs using CEU by destroying microbubbles and measuring their tissue replenishment with intermittent harmonic imaging. Both renal blood volume fraction and microbubble velocity were derived from pulsing-interval versus video-intensity plots. The product of the two was used to calculate renal nutrient blood flow. Renal arterial blood flow was independently measured with ultrasonic flow probes placed directly on the renal artery and was increased using dopamine and decreased by placement of a renal artery stenosis.

RESULTS

An excellent correlation was found between cortical nutrient blood flow using microbubbles and ultrasonic flow probe-derived renal blood flow (r = 0.82, p < 0.001) over a wide range (2.5 fold) of flows.

CONCLUSIONS

Ultrasound examination during microbubble infusion can be used to quantify total organ as well as regional nutrient blood flow to the kidney.

Abbreviations

BVF
blood volume fraction
CEU
contrast-enhanced ultrasound
NBF
nutrient blood flow
PI
pulsing interval
RBF
renal arterial blood flow
VI
video intensity

Cited by (0)

☆

Supported, in part, by grants from the National Institutes of Health, Bethesda, Maryland (RO1-HL48890 and R01-HL65704), the Mid-Atlantic Affiliate of the American Heart Association, Baltimore, Maryland (B98458V), the Fourjay Foundation, Williamsport, Pennsylvania and Bracco Diagnostics, Princeton, New Jersey. Advanced Technology Laboratories, Bothell, Washington, provided an equipment grant. Dr. Wei is the recipient of a Mentored Clinical Scientist Development Award (K08-HL03909). Dr. Le was the recipient of a NIH post-doctoral training grant (T32-HL07355), and Mr. Coggins was the recipient of a Medical Student Research Fellowship from the American Diabetes Association, Alexandria, Virginia.

Copyright © 2001 American College of Cardiology. Published by Elsevier Inc. All rights reserved.