Operating instructions

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Perfusion CT
After adjustment (use non-ischemic hemisphere as
guideline) ischemic areas will therefore be displayed
either in violet (very low flow) or as a mismatch with
the nonischemic side (gray matter is blue instead of
green).
– For “Time images” (Time to Start and Time to Peak) –
the color palette for the time images maps increas-
ing time values on a spectral scale:
Violet _ blue _ green _ yellow _ red
Display should be adjusted with the arrow buttons
such that the areas with latest arrival times are just
slightly red. As with the flow image black means no
calculation (CSF space, or areas with extremely low
flow – no time assessment possible).