Aortic surgery and horseshoe kidney: a challenging surgical problem.

Horseshoe kidney is a rare abnormality that complicates aortic surgery. Three such cases are presented and the literature is reviewed. Although the diagnosis was not made preoperatively in any patient, all were managed safely. Two patients required preservation of abnormal renal arteries and one required division of the renal isthmus for exposure. Special attention is drawn to the need for lateral angiographic projections of this condition and to the intraoperative injection of indigo carmine dye to delineate the proper line of division of the renal isthmus.