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artifacts may persist for a sustained
period in following images.
If imaging catheter has been placed
next to a relatively stationary and
bright tissue (e.g. calcified plaque),
moving the catheter away afterward
may create an artifact that may remain
on screen for a short time.
appears in area of
ringdown after
Adaptive NearVu is
activated
is based on the
assumption that
ringdown is relatively
stationary compared
stationary signals in the
image are likely to be
be gradually blanked
out over time
, within a
set radius in the image
of the IVUS catheter.
User should be extremely cautious when
imaging slow-moving tissues and
vessels. It is recommended to keep the
imaging catheter constantly moving
without being parked next to stationary
tissues.
Adaptive NearVu should not be used
when imaging stationary phantoms.
To avoid possible tissue blanking and
more importantly to prevent restricted
blood supply, it is very important to
avoid situations where the transducer is
barely moving and completely wedged
for a prolonged period in a heavily
blocked vessel. If catheter is wedged for
a long time, an artifact of a darkened
concentric circle may appear in and out
of image between cardiac cycles.
Potential Imaging Artifacts – Manual Ringdown Reduction, Manual NearVu
-like artifacts in
the area of ringdown
after
Manual NearVu
has been activated
(especially for PV
catheters).
An improper ringdown
reference was taken when
M
anual NearVu was
.
Avoid any tissues in the ringdown region
when the manual ringdown reduction is
toggled.
PV catheters only support the
manual mode of ringdown reduction, so any
poor
reference image that was accidentally
included will remain as an artif
act on the
screen until another reference is manually
taken.
Potential Imaging Artifacts – the ChromaFlo Feature
The ChromaFlo option provides a two-dimensional qualitative map of relative
blood flow velocities. Due to the qualitative nature, do not use this information
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