Carotid duplex scanning is a noninvasive, ultrasound test used on
the extracranial carotid artery (located in the neck) to determine
and detect occlusive disease directly. The duplex concept is based
on the ability to define the carotid artery walls within a
two-dimensional image and uses a pulse Doppler probe to evaluate
flow velocities with the artery. This technique can measure the
amplitude and the waveform of the carotid arterial pulse. Futhermore,
a two-dimensional image of the carotid artery can be produced. As a
result, one can directly visualize possible stenotic or occluded
arteries and the amount of arterial flow disruption. These are
important because by getting an image of these arteries and
determining if there is constriction or closure, complications such
as a stroke can be avoided. If arterial flow is blocked in the carotids,
then blood flow to the brain is diminished. This can lead to a
cerebral infarction (stroke).
