Staged coil embolization of extraparenchymal giant renal artery aneurysm with preservation of renal function

A 9-cm renal artery aneurysm near the primary bifurcation of the left main renal artery, which caused ischemic change and a small infarction in left renal anterior segment, was treated with staged coil packing of the aneurysm. Initial embolization with deployments of twelve 0.035-in. coils resulted in partial occlusion of the aneurysm and thickening aneurymal wall. Three months later after the initial embolization, packing of twenty-six 0.018-in. detachable coils achieved in occlusion of the aneurysm preserving contrast flow in near the neck and the posterior segmental artery. Both 3- and 1-year follow-up computed tomographic images, after the second session, confirmed no contrast flow in the aneurysm with restored contrast flow in the left kidney. This case indicates that staged coil embolization may be alternative to nephrectomy in patients with extraparenchymal giant renal artery aneurysms.