Stent

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For people named Stent, see Stent (surname).

In medicine, a stent is either an expandable wire form or perforated tube (conventionally perforated by means of laser cutting) that is inserted into a natural conduit of the body to prevent or counteract a disease-induced localized flow constriction.

1 Uses
2 Problems
3 Etymology
4 See also
5 External links

[edit] Uses

The main purpose of a stent is to overcome important decreases in vessel or duct diameter. Stents are often used to diminish pressure differences in blood flow to organs beyond an obstruction in order to maintain an adequate delivery of oxygen. Although the most common use of stents is in coronary arteries, they are widely used in other tubular structures, such as central and peripheral arteries and veins, bile ducts, oesophagus, colon, trachea or large bronchi, ureters, and urethra.

[edit] Problems

One of the weak points of vascular stents, however, is the development of a thick smooth muscle tissue inside the lumen, the so-called neointima. Development of a neointima is variable but can at times be so severe as to re-occlude the vessel lumen (restenosis), especially in the case of smaller diameter vessels, which often results in reintervention. Thus, there is a strong body of research focusing on the reduction of neointima after stent placement. Considerable improvements have been made, including the use of more bio-compatible materials, anti-inflammatory drug-eluting stents, resorbable stents, and others. Fortunately, even if stents are eventually covered by neointima, the minimally invasive nature of their deployment makes reintervention possible and usually straightforward.

[edit] Etymology

The origin of the word stent remains a matter of debate. The verb stenting was used for centuries for the process of stiffening garments (a usage long obsolete, per the OED) and some believe this to be the origin. Others attribute the noun stent to the English dentist Charles Stent (1807–1885), who invented a dental impression compound. The full account is described in the Journal of the History of Dentistry, which states: "The earliest use of the word 'stent' to describe this item was in 1916, when a Dutch plastic surgeon described how he used a dental impression compound as a matrix around which to form tissue in the process of rebuilding a shattered face." [1] Thus, according to the author, from the use of Stent's compound as support for facial tissues grew the eventual use of stent to open various bodily structures as described above.