Stenosis

A stenosis (plural: stenoses; from Ancient Greek στένωσις, "narrowing") is an abnormal narrowing in a blood vessel or other tubular organ or structure.

It is also sometimes called a stricture (as in urethral stricture).

The term coarctation is synonymous, but is commonly used only in the context of aortic coarctation.

Diagnosis
Stenoses of the vascular type are often associated with unusual blood sounds resulting from turbulent flow over the narrowed blood vessel. This sound can be made audible by a stethoscope, but diagnosis is generally made or confirmed with some form of medical imaging.

Causes

 * atherosclerosis causes stenotic lesions in arteries.
 * birth defects
 * diabetes
 * iatrogenic, e.g. secondary to radiation therapy
 * infection
 * inflammation
 * ischemia
 * neoplasm - in such cases, the stenosis is often said to be "malignant" or "benign", although this attribute actually refers to the neoplasm itself.
 * smoking
 * ureteral
 * urethral

Types
The resulting syndrome depends on the structure affected.

Examples of vascular stenotic lesions include:
 * Intermittent claudication (peripheral artery stenosis)
 * Angina (coronary artery stenosis)
 * Carotid artery stenosis which predispose to (strokes and transient ischaemic episodes)
 * Renal artery stenosis

The types of stenoses in heart valves are:
 * Pulmonary valve stenosis
 * Mitral stenosis
 * Tricuspid valve stenosis
 * Aortic valve stenosis

Stenoses/strictures of other bodily structures/organs include:
 * Pyloric stenosis (gastric outflow obstruction)
 * Lumbar, cervical or thoracic spinal stenosis
 * Subglottic stenosis (SGS)
 * Tracheal stenosis
 * Obstructive jaundice (biliary tract stenosis)
 * Bowel obstruction
 * Phimosis
 * Non-communicating hydrocephalus
 * Stenosing tenosynovitis