Evaluation of Renal Artery Anomalies Associated with Horseshoe Kidney Using CT Angiography.

PURPOSE To evaluate the incidence of supernumerary renal arteries in horseshoe kidney (HSK) patients, focusing on number and diameters using computed tomographic angiography (CTA). MATERIAL AND METHODS Thirty-nine patients with HSK and 103 patients with normal kidney (NK) underwent 64 or 128 multidetector CT. Based on 2-dimensional CT, including multiplanar reconstruction, maximum intensity projection, and volume-rendered images with a 0.5-mm reconstruction interval on CTA, we assessed the incidence of supernumerary renal arteries, and large ( > 3 mm in diameter) supernumerary renal arteries, and compared the results between the HSK and NK patients using a chi-square test. RESULT The mean number of renal arteries was 3.87 in HSK patients and 2.41 in the NK patients. The incidence rates of supernumerary arteries and supernumerary arteries greater than 3 mm were 92.3 %, 69.2 % in HSK patients and 33%, 8.7% in NK patients. Supernumerary and large supernumerary renal arteries had significantly higher incidence rates in the HSK patients than in the NK patients on CTA (p = 0.003, < 0.001). CONCLUSION Supernumerary and large supernumerary renal arteries were frequently found among the HSK patients on CTA.