Can Doppler Ultrasonographic Indices of the Renal Artery Predict the Presence of Supernumerary Renal Arteries?

Background: Variations of the renal arteries, including the presence of supernumerary renal arteries, are important to be identified prior to renal transplant. Angiography has been the gold standard test for the pretransplant evaluation of the renal vasculature. However, this modality is expensive and invasive. The aim of this study was to assess whether Doppler ultrasonographic (DU) indices of the renal artery could predict the presence of supernumerary renal arteries. Methods and materials: Retrospectively, we analyzed multidetector computed tomography angiography (presence or absence of the supernumerary renal artery), DU (peak systolic velocity, resistive index, pulsatility index, end-diastolic velocity, and acceleration time) findings of 30 healthy potential renal transplant donors. Recipient operator characteristic (ROC) curves were used to examine the predictive values of the available DU indices for supernumerary renal arteries. Results: The mean age of donors was 28.4 ± 4.1 years. Of 60 kidneys evaluated, a supernumerary renal artery was found in 10%. The ROC curve analysis revealed an area under the curve of noninformative (below 0.5) for all DU parameters, indicating that none of the studied parameters could predict the presence of a supernumerary renal artery. Conclusions: Although the smaller diameter of the main renal artery has previously been found to predict the presence of supernumerary renal arteries, the present study revealed that DU indices of the renal artery may not indicate the presence of supernumerary renal arteries.