Operating instructions

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HeartView CT
The preview series should be used to define the opti-
mal time window for image reconstruction in ECG-
gated spiral scanning, before the full series is recon-
structed.
A default value of 60% relative gating (or -400 ms
absolute reverse gating) can be used as an initial set up
for the optimization process which is best performed
as follows:
• Select an image level displaying the mid RCA.
• Choose 60% (or -400 ms) reconstruction phase set-
ting.
• Reconstruct a preview series at this level of the RCA
by clicking on the Preview Series button in the Trig-
ger tabcard: a series of images with different phase
settings at the selected anatomical level of the RCA
will be reconstructed.
• Choose the image with least motion artifacts.
• Reconstruct the whole data set with the phase set-
ting you selected. Please note that you have to enter
this phase setting manually in the Trigger tabcard.
An example for a preview series at the correct anatom-
ical level with optimal and sub-optimal selection of the
phase setting is shown below. Usually this procedure
results in good image quality for the right and the left
coronary artery, especially at higher and inconsistent
heart rates individual optimization for left and right
coronary artery may be necessary. In most cases, the
RCA requires an earlier phase in the cardiac cycle to
obtain the period of least motion, e.g. RCA at 40%, LAD
at 60%.