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Figure 6 In-Vitro Investigation of Sources of Error

(Top) Long-axis cut plane extracted form a RT3DE dataset of an egg-shaped phantom, shown with the boundary traced along the interface (A), after expanding the boundary 1 mm outward (B), and with both boundaries (C). Interestingly, the small difference between the 2 boundaries resulted in an 11% difference in the measured volume of the 3D shell (see text for details). (Bottom) Cross-sectional views of a water-filled latex balloon with 3 alternative manually traced boundaries: along the inner interface (D), along the outer interface (E), and in the center of the latex layer (F). Volumes (V) resulting from each tracing session are shown to be compared with the true volume of 150 ml. Abbreviations as in Figure 1.