FIG 4. Images of a 70-year-old man with MCA occlusion at horizontal part. Digital subtraction angiogram (D) shows that territory of ACA has spread wide into the lateral area (arrow). Area with ACA perfusion is larger in the tilted plane than in the images shown in Figures 2 and 3 (86% on plane A, 78% on plane B, and 79% on plane C). Color scale shows t values.