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Bolus Tracking
Application Procedures:
1. Select the spiral mode that you want to perform,
and then “Append” the TestBolus mode under Special
protocols.
2. Insert the Test Bolus mode above the spiral mode
for contrast scan by “cut/paste”(with right mouse
button).
3. Perform the Topogram, and define the slice position
for TestBolus.
4. Check the start delay, number of scans and cycle
time before loading the mode.
5. A test bolus with 10-20 ml is then administered
with the same flow rate as during the following spiral
scan. Start the contrast media injection and the
scan at the same time.
6. Load the images into the Dynamic Evaluation
function and determine the time to the peak enhance-
ment.
Alternatively, on the image segment, click “select series”
with the right mouse button and position an ROI on
the first image. This ROI will appear on all images in
the test bolus series. Find the image with the peak HU
value, and calculate the time “delta t” taken to reach
the peak HU value (do not forget to add the preset
start delay time). This time can then be used as the
optimal start delay time for the spiral scan.