fig 2.

CBF maps of the same patient shown in figure 1 show perfusion CT studies of CBF (cc/[100 g × min]). The three CBF maps agree and show a 20% decrease in the left CBF. Cerebral regions with normal (blue ROI) and lowered (green ROI) CBF values are adequately displayed on the three CBF maps. With the LMS perfusion CT software, pixels with ACA and MCA branches (red ROI) show discretely increased CBF values, whereas they are filtered away with the SVD perfusion CT software. SVD and LMS perfusion CT software differ regarding the detection thresholds of vessels and spatial filtering for the final display.

A, Stable xenon CT scan.

B, SVD method.

C, LMS method