Transcatheter arterial embolization in patients with kidney diseases: an overview of the technical aspects and clinical indications

Abstract

Therapeutic embolization is defined as the voluntary occlusion of one or several vessels, and this is achieved by inserting material into the lumen to obtain transient or permanent thrombosis in the downstream vascular bed. There are a number of indications for this approach in urological practice, in particular for the patients with parenchymatous or vascular kidney disease. In this review, we present the different embolization techniques and the principally employed occluding agents, and then we present the principal clinical indications and we discuss other pathologies that may benefit from this non-invasive therapy. The complications, side effects and main precautions associated with this approach are also described.

Keywords: Arterial embolization; Interventional radiology; Kidney; Surgery.

Fig. 1

Preoperative glue embolization of renal cell carcinoma before nephrectomy in 69-year-old man. A. Selective renal arteriogram: large vascular tumor in lower-pole of left kidney. B. Control angiogram after embolization of entire renal artery using radiopaque cyanoacrylate/Lipiodol mixture (1:3): complete occlusion of renal artery allows minimal intraoperative blood loss and easier nephrectomy.

Fig. 2

Recent lumbar pain in 19-year-old patient with Bourneville's tuberous sclerosis. A-C. CT scan (A) and arteriography (B, C) confirm modifications of renal vascular architecture, as related to fat infiltration and making upper-pole mass opaque (arrowheads) and mass corresponds to hemorrhagic angiomyolipoma. Vascularization of angiomyolipoma is ensured by atypical artery (arrow). D. Results after superselective embolization with 300-500 µm calibrated microspheres using 3 Fr microcatheter: angiomyolipoma is completely devascularized without infarction of renal parenchyma. E. CT scan at one year shows evolution of disease with predominant fat infiltration, but no hypervascularization.

Fig. 3

Preventive embolization of large renal angiomyolipoma in 63-year-old woman. A. Aortography showing round, well-defined intraparenchymatous mass 4 cm in diameter in upper pole of right kidney (arrowheads). B, C. Selective renal angiogram confirms hypervascularized character of angiomyolipoma. D, E. Final angiography after using 300-500 µm microspheres to superselectively embolize two main arterial branches with using 3 Fr microcatheter: devascularization of entire angiomyolipoma (arrowheads) with respect to rest of renal parenchyma.

Fig. 4

Emergency embolization for arterial injury after blunt renal trauma in 51-year-old woman. A. Extravasation of contrast medium (pseudoaneurysm-like lesion) from lower distal-pole branch at selective angiography indicates continuous bleeding (arrow). B. Selective embolization of feeding artery using detachable microcoils. C. Control angiogram shows complete and selective occlusion of bleeding branch, with no active bleeding.

Fig. 5

Massive hematuria with hypovolemic shock two hours after performing percutaneous renal biopsy in 56-year-old woman. A, B. Presence of high-flow arteriocaliceal fistula on emergency renal angiography with rapid opacification of urinary cavities. C. Microcoil embolization of two abnormal vessels that were responsible for hematuria. D. Complete occlusion of fistula and cessation of bleeding are seen on post-embolization angiogram.

Fig. 6

Progressive arterial hypertension in 43-year-old patient one year after percutaneous renal allograft biopsy. A. Selective arterial angiogram: there is large arteriovenous fistula in upper-pole segmental branch of transplanted renal artery and pseudoaneurysm (black arrow) with marked arteriovenous shunting (arrowheads) and early venous filling (white arrow). Note absence of nephrogram. B. Control angiogram after selective embolization of afferent artery with 0.035" coils: complete occlusion of pedicular aneurysm and fistula, and improvement in nephrogram. C. Post-embolization angiogram (parenchymal phase): renal infarction is seen in less than 10% of renal parenchyma (arrows).

Fig. 7

67-year-old man with asymptomatic renal artery aneurysm that was incidentally discovered on CT scan of abdomen. A. Selective arteriogram demonstrating filling of saccular renal aneurysm arising from hilar branch. B. Control angiography after embolization of aneurysmal sac across neck with detachable fibered microcoils and using packing technique: there is near complete occlusion of aneurysm and preservation of main renal artery.