Arteriography before needle puncture or renal hilar lesions

We report on 2 patients with cystic-appearing lesions in the renal hilus that were detected on urography. In 1 case an ultrasound study confirmed a cystic mass but an arteriogram revealed a renal artery aneurysm. The arteriogram before the contemplated puncture of the renal hilar mass prevented an inadvertent puncture. The information about the arterial anatomy helped preoperative planning, which resulted in successful repair of the aneurysm by microdissection and autotransplantation.