Fig. 2. Regions of statistically significant decreases (  A ) and increases (  B ) in absolute regional cerebral blood flow in voxel-based analysis. The height threshold (T) was set to 3.0, and the extend threshold (k) was set to 500 (  A ) and 1,000 (  B ). See Materials and Methods, Data Analysis, Voxel-based Image Analysis for details. The stereotactic coordinates are presented in  tables 1 and 2 on the Anesthesiology Web site.