What is the typical patency rate duration for plastic stents?

Plastic stents are commonly used in various endoscopic procedures, particularly for biliary and gastrointestinal obstruction. Their design and material can lead to a variable patency rate, which refers to the duration that the stent remains open and functional without blockage.

The typical patency duration for plastic stents is generally around 2 to 6 months. This duration is influenced by factors such as the patient's underlying condition, the stent's material properties, and the presence of biofilm or tissue ingrowth. Over time, plastic stents can become occluded due to factors like mucosal hyperplasia and tissue in-growth, which can significantly reduce their effectiveness.

While other choices reflect longer durations, they do not correspond to the commonly observed clinical experience with plastic stents, as their patency rates typically do not exceed 6 months without requiring exchange or replacement. Consequently, the range of 2-6 months accurately describes the expected longevity of plastic stents in practice.