Stent-Assisted Coil Embolization of Wide-Neck Renal Artery Aneurysm
in a Patient with Single Kidney

Authors: Myungsu Lee

Clinical History

A 46-year old female was found to have a left renal artery aneurysm on abdominal ultrasonography during health check up. The patient also had IVC duplication and right renal agenesis. On CT and angiography, the aneurysm was wide-necked and 22 x 18-mm sized, and located adjacent to left renal artery bifurcation site. Concerning renal function and anatomic property of the aneurysm, stent-assisted coil embolization was planned. After right CFA puncture, 7F renal guiding sheath was inserted and after 6 x 30-mm Solitaire stent (EV3, Irvine, CA, U.S.A.) was deployed at posterior segmental artery. Subsequently micro-catheter was negotiated into the aneurysm sac via stent cell, and coil embolization was performed with a 20 x 500-mm Axium 3D detachable coil (EV3, Irvine, CA, U.S.A.) and 18 10 x 300-mm Interlock detachable coils (Boston Scientific, Marlborough, MA, U.S.A.). After completion of embolization, flow to the posterior segmental artery was preserved and there was no hypo-perfused area in renal parenchyma on left renal angiography.

Figure 1

Contrast enhanced CT scan showed a 22 x 18-mm sized aneurysm at left renal artery. There was focal calcification on the wall of the aneurysm. Right renal agenesis and IVC duplication were incidentally diagnosed.

Figure 2

On angiography, the aneurysm located adjacent to left renal artery bifurcation. On 3D angiography, the neck of the aneurysm was wide-necked.

Figure 3

After deployment of Solitaire stent (EV3, Irvine, CA, U.S.A.), micro-catheter was negotiated into the sac. Subsequently coil embolization was performed and on completion angiography, all the branch of left renal artery was patent and there was no hypo-perfused area in renal parenchyma.

Renal artery aneurysm (RAA) is rare disease which can be caused by trauma, infection, arteritides, Kawasaki disease, or vascular dysplasias. Symptomatic RAAs can cause hypertension, flank pain, haematuria and renal infarction, and these are indications for treatment. Large (>2cm diameter) or enlarging RAAs have high risk of rupture and also should be treated. Other indications for treatment include rupture, aneurysms in females contemplating pregnancy and aneurysms associated with dissection. Several surgical or endovascular method can be recruited for treatment. The patient had RAA adjacent to the renal artery bifurcation and had wide neck. For endovascular treatment of RAAs, parent artery embolization or stent-graft placement are possible options. Parent artery embolization is not feasible for RAAs in central location as it can sacrifice large portion of the kidney. Stent-graft placement is not also feasible for the patient as the aneurysm was near the bifurcation of renal artery. Coil embolization of the aneurysm sac was treatment of choice for the patient and due to wide neck stent-assisted embolization was performed. Stent-assisted coil embolization of aneurysm sac is commonly used technique in treatment of cerebral aneurysms, which can protect parent artery from dislodgement of coils despite of wide neck.