First 301 words of the document:
What is a stent? What is it used for? Ben Fenton
A stent is a tube that is made of plastic or metal. It is inserted into a blood vessel (artery or vein) or passage way in the
human body to keep it open. A stent will stop a passageway/ blood vessel from collapsing due to external pressure,
build-up of fatty substances or deposits or tightening. If a stent is not fitted, total blockage can occur and cause a
heart attack or blocked passageway.
A stent is a permanent implant. It is put into the correct place and then expanded against the wall of the tube where
there is often a build-up of fatty substances that are stopping the smooth flow of blood/food etc. It locks into place and
forms a rigid support.
Stents are most often used for these reasons:
to keep blood vessels open in the heart arteries (coronary arteries)
to keep the oesophagus wide enough for food to travel down if there is cancer blocking the oesophagus
to keep the tubes that carry urine from the kidneys open (ureter)
to keep the bile duct in the pancreas open if they keep getting blocked.
This illustration shows the
increased flow of blood once
a stent has been placed in
a cardiac vessel.
The picture below shows the process
involved in fitting a coronary vessel stent. A thin plastic tube covered with a small balloon is passed into the heart
artery. The balloon is then inflated and this clears any small blockages. The balloon is then deflated and removed,
leaving the stent. The stent is often coated with drugs which stop infection setting in after the procedure.