Stents and Atherectomy Devices
A stent is a device used
to open obstructed blood vessels without the need for surgery. A wire
is threaded through the blocked artery via a needle stick. Once the
wire is across the blockage, a collapsed balloon and stent are passed
over the wire, the balloon is inflated, and the stent is expanded or
deployed. This crushes the obstructing plaque, and it is kept from reforming
and obstructing the artery by the stent. Stents can be used for blocked
arteries in many places in the body . Below left is an arteriogram
of a patient with complete obstruction of the artery going to the left
leg, causing severe pain on walking.
After the patient unwent successful stenting of the artery, the picture
at right shows that the obstruction to blood flow has been completely
relieved. 
In some cases
the plaque is so extensive that simple stenting is not an option. In
some patients, the plaque can actually be removed using an atherectomy
device, pictured at left. 
Using
multiple passes through the blocked artery, pieces of plaque are cut
by this device (known as an atherectomy catheter) and can be removed
from the inside of the artery. A sample of the material removed by this
device is pictured at right. In this way, small arteries, not usually
successfully treated by stenting or conventional surgery for perihperal
artery disease can be opened, restoring blood flow to the affected
limb.