What Are The Different Types of Biliary Stents?

There are several types of biliary stents used to open blockages in the bile ducts: Plastic stents:

- Polyethylene stents - A most common type of plastic stent. Relatively inexpensive but higher risk of clogging over time.

- Teflon stents - Made of PTFE material. Lower risk of clogging compared to polyethylene.

Metal stents:

- Uncovered self-expanding - Made of materials like nitinol or Elgiloy. Expands on its own when deployed. Higher patency but tissue can grow through.

- Covered self-expanding - Covered in a membrane to reduce ingrowth. Better for benign strictures.

- Balloon expandable - Expanded with a balloon to a precise diameter. Effective for hilar blockages. 

- Drug-eluting - Metal stents that have a drug-coated layer to reduce ingrowth.

Specialty stents:

- Magnetic - Contain magnets to approximate stent ends together. Useful for leaks/fistulas. 

- Biodegradable - Made of materials that dissolve over time. Avoid long-term stent complications.

- Antireflux - Valve or ducts to prevent reflux while allowing bile flow. Helpful for gallbladder problems. 

The stent choice depends on the location and nature of the blockage, expected duration, and patient factors. Gastroenterologists select the optimal type and size to treat the stricture while minimizing complications.