Embolization Agents—Which One Should Be Used When? Part 2: Small-Vessel Embolization

In Part 1 of this two-part article, we discussed commonly used large-vessel embolic agents and clinical scenarios in which the agents might be used. We also discussed how to choose between the multitude of embolic agents that are currently commercially available. In this article, we will focus on embolic agents used to occlude small vessels and when to choose which agent.

It is vital to recognize one important characteristic of all embolic agents: regardless of composition, the smaller the agent, the greater the likelihood of organ ischemia. Most organs have some duplication of vascular supply; this collateralization is vital to organ survival following a proximal vascular event. If very small embolic agents are used, the effective level of the embolization is distal to where the collateral vessels join the main feeding artery, thereby effectively occluding inflow from both the primary and collateral circulations. Therefore, for most organ systems, small agents cause much greater ischemia than larger agents.

SUGGESTED READINGS

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