What is kidney embolization?

From the Guidelines

Kidney embolization is a minimally invasive procedure that deliberately blocks blood vessels in the kidney to stop blood flow to a specific area, and it is commonly used to treat kidney tumors, control bleeding, manage symptoms of kidney cancer before surgery, or eliminate abnormal blood vessel connections, as indicated in the WSES-AAST guidelines 1.

Procedure Overview

The procedure involves a radiologist inserting a catheter through a small incision, typically in the groin, and guiding it through blood vessels to the kidney using imaging guidance. Once positioned, embolic materials such as tiny particles, coils, or special glue are injected to block the targeted blood vessels.

Indications and Considerations

The indications for kidney embolization include arterial contrast extravasation on CT-scan in hemodynamically stable or transient responder patients, gross non-self-limiting hematuria, arteriovenous fistula, pseudoaneurysm, and extended perirenal hematoma, as outlined in the guidelines 1. The procedure should be performed as selectively as possible to limit the associated parenchymal infarction, and the choice of embolic agents depends on the type of vascular injury 1.

Outcomes and Complications

The overall success rate of kidney embolization in blunt renal trauma ranges from 63% to 100%, and the procedure has lower complication rates compared with surgery, with a reported morbidity rate of 25% 1. The complications may include accidental embolization of healthy arterial branches, puncture-site bleeding, arterial dissection, and thrombosis, among others.

Recommendations

In hemodynamically stable or stabilized patients with solitary kidney and moderate or severe renal trauma with arterial contrast extravasation on CT-scan, angiography with eventual super-selective angioembolization should be considered as the first choice, as recommended by the guidelines 1. The procedure should be performed in a specialized center with immediate availability of operating room, surgeon, adequate resuscitation, and high dependency/intensive care environment.

From the Research

Kidney Embolization Procedure

The kidney embolization procedure, also known as renal artery embolization, is a minimally invasive technique used to treat various conditions affecting the kidneys.

• The procedure involves the use of embolic materials, such as metal coils, sclerosants, and particulate embolic agents, to block blood flow to specific areas of the kidney 2.
• The main indications for renal artery embolization include:
  • Preoperative infarction of renal tumors
  • Management of renal angiomyolipomas
  • Palliation of unresectable renal malignancy
  • Renal hemorrhage
  • Arteriovenous fistulas
  • Vascular malformations
  • Renal artery aneurysms and pseudoaneurysms 2, 3, 4.
• The procedure can be performed alone or in combination with other techniques, such as remodeling, stent-grafting, and balloon- or stent-assisted coiling 2.
• Renal embolization is considered a safe and effective treatment option for various urologic conditions, including malignant renal tumors, angiomyolipomas, renal trauma, and complications following biopsy 3, 5, 6.

Techniques and Embolic Agents

• Various embolic agents are available, including gel foam, which has been shown to be a relatively inexpensive, safe, and effective option for treating life-threatening renal hemorrhage 5.
• The choice of embolic agent depends on the clinical application, technical and clinical endpoints, as well as the pathology of the lesion being targeted 2.
• The procedure is typically performed by interventional radiologists, and a multidisciplinary approach between urology and interventional radiology is recommended for optimal outcomes 3.