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– Move the monitoring scan line toward the optimal
position and release the mouse button, it will be
snapped automatically. (Trick: if you move the mon-
itoring scan line away from the optimal position the
snapping mechanism will be inactive).
4.Place a ROI in the premonitoring scan on the target
area or vessel used for triggering with one left
mouse click. (The ROI is defined by double circles–
the outer circle is used for easy positioning, and the
inner circle is used for the actual evaluation). You
can also zoom the reference image for easier posi-
tioning of the ROI.
5.Set the appropriate trigger threshold, and start con-
trast injection and monitoring scans at the same
time.
The relative enhancement of the target ROI will be
displayed for the duration of the monitoring scan.
When the predefined density is reached, the spiral
acquisition will be triggered automatically.
6.You can also initiate the spiral any time during the
monitoring phase manually – either by pressing the
START button or by left mouse clicking the START
radio button. If you do not want to use automatic
triggering, you can set your trigger threshold num-
ber extremely high so that it will not trigger auto-
matically and start the spiral when you want to.