Color-encoded perfusion maps before, during, and after aliskiren (ALI). Calculated perfusion map with color-encoding before (A; pre-ALI), during (B; ALI), and after (C; post-ALI) treatment with ALI. White, perfusion <3 or >600 ml/min per 100 g; blue, perfusion <100 ml/min per 100 g; yellow, perfusion >100 and <250 ml/min per 100 g; red, perfusion >250 and <600 ml/min per 100 g.