Which material is described as having poor memory, reduced thrombogenesis, and being easy on tissue insertion?

• A. Teflon
• B. Polyurethane
• C. Polyethylene
• D. Polypropylene

Answer: (B)

Material choices for intravascular devices are judged by how they handle in the body: how much they remember their shape (memory), how likely they are to promote clot formation (thrombogenesis), and how gently they interact with tissue during insertion. A polymer with poor memory stays flexible and doesn’t snap back into a rigid shape, which helps it navigate vessels without kinking. It also tends to be smoother and more forgiving to tissue, reducing trauma during placement. At the same time, a surface that minimizes clot formation lowers the risk of thrombosis. Polyurethane fits these needs well: it’s soft and elastic, has low shape memory that favors easy insertion, and provides a biocompatible surface that reduces thrombogenic potential. The other polymers listed are typically stiffer or less forgiving in contact with blood and tissue, making them less optimal for easy, low-trauma insertion with reduced clot risk.