A stenosis or stricture is an abnormal narrowing in a blood vessel or other tubular structure in the body.
When the stenosis occurs in a blood vessel, the blood passing through the stenosis will have a turbulent flow. The sound of this turbulence can often be picked up on a stethoscope, but most are confirmed through the use of some form of medical imaging.
A stenosis can have several causes. Atherosclerosis is the most common, but diabetes mellitus, infection, inflammation, ischemia and smoking can all be causes.