Interventional Radiology Equipment: Guidewires


This page serves as a guide to various types of guidewires that are used within the field of interventional radiology. There are many different types of wires and it can be overwhelming to learn about all of them without an organized approach!

Many different wires are used in IR, it is important to appreciate what makes each wire so unique (image source).

There are many different types of wires that are used in interventional radiology however they aim to serve a few key roles:

  1. Access wires: wires used temporarily to gain access into vessels/structures, often times quickly exchanged for other types of wires.
  2. Maneuvering wires: used to gain entry into difficult to access vessels or structures. They are often floppier, hydrophillic, and can have curved tips for selecting/subselecting vessels.
  3. Rail wires: these are more secure wires that are used as support for conducting interventions (advancing devices etc). Generally they are stiffer wires that will more easily maintain access while interventions are being performed.

Each wire has a few key characteristics that define what it is and its utility for procedures.

  • Diameter: the thickness of the wire
  • Stiffness: how floppy or rigid the wire is
  • Hydrophobic/hydrophilic nature: The material of the wire will dictate this property. Hydrophilic wires can slide more easily when wet, hydrophobic wires will not slide as easily.
  • Tip shape: the tip of the guidewire can have its own unique shape (straight, curved, etc).
  • Length: the same type of wire can come in different lengths which may dictate what the wire can be used for.

There are two common diameters of guidewires that are used: a 0.018 inch diameter wire and a 0.035 inch diameter wire.

Some important considerations to keep in mind when using these wires: 

  • A 22 gauge needle is the smallest that can be used for a 0.018 inch diameter wire
  • A 18 gauge needle is the smallest that can be used for a 0.035 inch diameter wire

The stiffness of various wires is a spectral characteristic..


This feature of the wire will dictate its behavior when the wire is made wet.

Hydrophillic wires: these wires are most useful in situations where less resistance is needed. They become slippery when wet which makes them easier to slide past points of resistance (however also makes them difficult to grip). They need to be flushed regularly because they become sticky when they are dry. Torque devices can be used







Page Updated: 02.25.2019