GE LOGIQ V3, Basic Service Manual

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Functional checks
LOGIQ V3/V5/V5 Expert – Basic Service Manual 4-37
5726264-100 English Rev.8
4-3-25 Adjust the TVI Controls
• To reduce quantification noise (variance), the Nyquist limit
should be as low as possible, without creating aliasing. To
reduce the Nyquist limit: Reduce the
Scale value.
NOTE: The Scale value also affects the frame rate. There is a trade
off between the frame rate and quantification noise.
TVI provides velocity information only in the beam direction.
The apical view typically provides the best window since the
beams are then approximately aligned to the longitudinal
direction of the myocardium (except near the apex). To
obtain radial or circumferential tissue velocities, a
parasternal view must be used. However, from this window
the beam cannot be aligned to the muscle for all the parts of
the ventricle.
NOTE: PW will be optimized for Tissue Velocities when activated
from inside TVI.