Renal Volumetry-based Prediction of the Presence of Accessory Renal Artery: Computed Tomographic Angiography-based Study with Clinical Implications on Renal Doppler

BACKGROUND: The objective was to validate the hypothesis and evaluate whether the presence or absence of accessory renal artery can be predicted on the basis of volumetric parameters of kidney and diameter of the main renal artery (mRA). METHODS: This retrospective analysis was performed in a total of 60 kidneys in 30 patients, who had computed tomographic (CT) angiography. The kidneys were segregated into control and study groups depending on the absence or presence of accessory renal artery. The total renal volumes were measured using renal length, breadth, and height in mm(3). The renal artery diameters were also measured in mm, in the postostial segment. Renal volume/renal artery diameter (V/d) was measured for each kidney in two groups, and the difference in mean V/d values (in mm(2)) in two groups was measured for statistical significance. RESULTS: The mean V/d value in the study group with presence of the accessory renal artery was found to be 23,444.7 mm(2) (range: 16,229.1–32,490.0). The V/d value in the control group with the absence of accessory renal artery was found to be 19,717.15 mm(2) (range: 13,704.6–28,000.0). The mean values in the two groups showed a statistically significant difference in the V/d with a P value of 0.001 (P < 0.05). CONCLUSION: The study suggests that the possibility of the presence of the accessory renal artery is directly proportional to the total renal volume and inversely proportional to the diameter of mRA. The use of integrated volumetric parameter (V/d) is therefore likely to play a key role in the prediction of the presence of accessory renal artery on imaging studies. Renal volumetry on CT angiography may help predict the presence of accessory renal artery and thus may have implications on renal Doppler studies.