Fig. 4
From: A new tissue segmentation method to calculate 3D dose in small animal radiation therapy
ρZeff variation with absorbed dose in ICRU tissues (see Table 1). MC dose calculations were performed for an anterior 5 mm 225kVp beam in a 5x5x5cm3 water tank with a 5 mm thick tissue insert at 1.5 cm depth in water. Absorbed dose in tissue was normalized to absorbed dose at the same position in the homogeneous water tank. This plot shows that a 0.2 ρZeff interval between two neighboring tissues is required to reach approximately 2% dose calculation precision