FIGURE 2. (A) Phantom used in computer simulations. Bright small ellipses correspond to simulated kidneys. Large ellipse representing body outline is divided into left body background (LB) and right body background (RB), which have different intensity levels (shown as different shades). Rectangles encompass ROIs used for time–activity curve extractions. (B) Image of left kidney (LK) in canine study superimposed on attenuation map approximately 4 min after injection. Rectangular regions correspond to ROIs used for extraction of time–activity curves of LK (small 3-pixel ROI) and background (large 50-pixel ROI). Dog was positioned off-center during experiment.
