Embolic particles: what blocks the blood flow

Embolic particles

Embolic particles, also called embolic agents, are tiny materials put into an artery through a catheter to block blood flow to a target¹. In uterine fibroid embolization (UFE), they cut off the blood supply that feeds the fibroids, so the fibroids shrink¹. The same idea is used in prostate and knee embolization.

A plain-language definition from the ProcedurePath glossary.

Written and reviewed by Varun Danda, MD, interventional radiology resident physician · Last reviewed October 25, 2026

Common types

Polyvinyl alcohol (PVA): a plastic material that looks like coarse sand.
Gelatin sponge: a sponge material made from gelatin.
Microspheres: small round beads with a gelatin coating.

RadiologyInfo lists these three types for UFE¹.

Why the type matters

Particles come in different sizes and shapes. Your doctor picks the type and size for the arteries being treated. You can ask which particles they plan to use and why.

Common question

What are embolic particles made of?

Common types include polyvinyl alcohol, a plastic that looks like coarse sand, gelatin sponge, and gelatin-coated microspheres¹.

Talk with your doctor before you decide. This information does not replace personal medical advice. Read the medical disclaimer.

Sources

RadiologyInfo.org (ACR/RSNA), uterine fibroid embolization ↩︎