For test bolus use:
10 ml Contrast - 6 ml/s
50 ml Saline - 5 ml/s
Then measure DELAY in DYNEVA software. Set 10 s to the "delay from the start" button and Drag and drop "Test bolus 10 B40" to DYNAEVA software and put the oval ROI to the ascending aorta. Then you will get TIME TO PIK (TTP). Add 2 seconds to TTP which will make your actual delay time for Coronary CTA.
First make a tomogram. Position the patient in feet first direction. Use the green cath in the antecubital vein. Plan the external laser on the chin. Then push the button - move patient to the scan area.
After topogram make a Calcium Scoring (Fl_CaSc). When you do calcium score you need to cover from the carina until the end of the heart.
So, do the Flash check before the scan and scan as it is.
Then you have to plan your Test Bolus.
Starting point for the test bolus and coronary CTA is not like in Calcium Scoring. It is slightly lower. To find the upper starting point for test bolus and for CTA first find LAD, then go few slices up until you do not see it, then continue going up counting till 10. It is approximately will be at the level of aorta and truncus pulmonalis bifurcation. The end of the test bolus - find the lowest part of the heart and go down counting 10 slices. The starting point for coronary CTA must be exactly in the test bolus level.
For the test bolus delay is always 10 s and this do not requires any instructions. Just press start scan and inject the test bolus contrast simultaneously. Wait until 4 images. You will see arrival of the contrast to the ascending aorta -- pik of contrast in the aorta -- and departure of contrast in the ascending aorta. Remember that DUNA evaluation software requires minimum 4 images.
Then measure DELAY in DYNEVA software. Set 10 s to the "delay from the start" button and Drag and drop "Test bolus 10 B40" to DYNAEVA software and put the oval ROI to the ascending aorta. Then you will get TIME TO PIK (TTP). Add 2 seconds to TTP which will make your actual delay time for Coronary CTA. If your TTP will be equal to 10 s add 2 seconds. Will make 12 s. But you see in our protocol CCTA the minimum delay time is 15 seconds. So here you have 3 seconds longer than your actual delay. But anyway you can keep it as 15 seconds.
If the heart rate is more than 80 bpm chances you have a good images is only in sistoly. So put bestsystoly. If your heart rate is lower than 75, then change it to best diastoly.
Do the spiral scan if the heart rate is more than 75 bpm. Spiral scan means you have scanned from 0% till 100%.
We have the protocols to image the coronaries: