Assessment of intrarenal perfusion with radioxenon: a critical review of analytical factors and their implications in man.

Radioxenon has achieved wide use for assessing tissue perfusion. Here we review its application to the kidney for assessing mean blood flow and intrarenal perfusion rates. Correlation with alternative methods in animals suggests that the initial disappearance slope provides an adequate measure of mean renal blood flow despite the theoretical limitations of this approach. The stochastic method and compartmental analysis can also provide an acceptable measure fo mean renal blood flow, but only after the slowest flow components have been removed. Compartmental analysis does, however, provide an index of cortical perfusion not available from other methods. The evidence that the rapid component of xenon washout provides an index of cortical perfusion in man is reviewed, along with insights gained from the application of this approach to human disease.