Embolic Agents: Coils

Catheter-directed embolization is one of the cornerstones and defining procedures of interventional radiology. Armed with a plethora of agents and devices, interventionalists can acutely stop flow, usually of a blood vessel, to effectively treat pathologies from head to toe. The list of pathologies treatable by embolization is extensive and diverse, including life-threatening hemorrhage, aneurysms, lymphatic duct leaks, varices, pelvic congestion syndrome, benign prostatic hyperplasia, uterine fibroids, and cancer.

Coils are arguably one of the most important embolization agents due to their ease of use, visibility on fluoroscopy, and ready availability. Coils are made from steel or platinum and offer permanent occlusion when deployed. They come in a wide range of shapes, sizes, coating materials, and deployment methods which can be used for effective target embolization in a variety of scenarios. The aim of this article is to provide a general back-to-the-basics overview of coil embolization. We discuss the historical development of coils as an embolization material, the numerous various coil types and their respective advantages/disadvantages, as well as general clinical and technical considerations when utilizing coils for embolization.

Disclosures/Conflicts of Interest

None declared.

Publication History

Article published online:
18 February 2022

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