Sampling Inspection

It is recommended to briefly inspect the TACs. They are shown in the REST Input or STRESS Input tabs on the Kinetic Modeling page.

The following should be checked:

• The RV TAC appears first and typically shows the highest peak of all curves.
• The LV TAC shows a clear peak and then drops below the myocardial activity. Note that the curve shapes depend on the speed of the bolus injection and the heart activity.
• If some of the myocardial TACs have a very similar shape as the LV TAC this indicates that their VOIs include too high a fraction of the LV blood pool.
• Make sure that the timing is right; if it is not correct for some reason (eg. processing data which does not include the timing information), the kinetic modeling will fail or return invalid results!

Note that for a closer inspection of the curve shapes you can zoom into the curve display by dragging a rectangle using the left mouse button. An alternative is to click with the right mouse button into the curve area and then select the View in Separate Window entry of the context menu.

If the data is not convincing, please return to the VOI outlining step and correct. A problem occasionally seen and difficult to correct is, that a patient moved, so that in the early frames the VOIs are not aligned with the myocardial position throughout the whole acquisition.